CELYAD S.A. (SEC Filing Page | XBRL Cloud Viewer | XBRL Instance)

Line Label Object Class Period Type Balance Report ElementName
1 1001 - Document - Document and Entity Information Network

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3 Document and entity information [abstract] Abstract cyad:DocumentAndEntityInformationAbstract
4 Document Type Concept (Submission Type) For Period dei:DocumentType
5 Amendment Flag Concept (Yes/No) For Period dei:AmendmentFlag
6 Document Period End Date Concept (Date) For Period dei:DocumentPeriodEndDate
7 Document Fiscal Year Focus Concept (Year) For Period dei:DocumentFiscalYearFocus
8 Document Fiscal Period Focus Concept (Fiscal Period) For Period dei:DocumentFiscalPeriodFocus
9 Trading Symbol Concept (Text/String) For Period dei:TradingSymbol
10 Entity Registrant Name Concept (Text/String) For Period dei:EntityRegistrantName
11 Entity Central Index Key Concept (CIK Number) For Period dei:EntityCentralIndexKey
12 Current Fiscal Year End Date Concept (Month/Day) For Period dei:CurrentFiscalYearEndDate
13 Entity Well-known Seasoned Issuer Concept (Yes/No) For Period dei:EntityWellKnownSeasonedIssuer
14 Entity Current Reporting Status Concept (Yes/No) For Period dei:EntityCurrentReportingStatus
15 Entity Filer Category Concept (Filer Category) For Period dei:EntityFilerCategory
16 Entity Emerging Growth Company Concept (Yes/No) For Period dei:EntityEmergingGrowthCompany
17 Entity Ex Transition Period Concept (Yes/No) For Period dei:EntityExTransitionPeriod
18 Entity Shell Company Concept (Yes/No) For Period dei:EntityShellCompany
19 Entity Common Stock, Shares Outstanding Concept (Shares) As Of dei:EntityCommonStockSharesOutstanding
20 1003 - Statement - Consolidated Statements of Financial Position Network

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21 Implied Table Table

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22 Statement of financial position [abstract] Abstract ifrs-full:StatementOfFinancialPositionAbstract
23 NON-CURRENT ASSETS Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssets
24 Intangible assets Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
25 Property, Plant and Equipment Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
26 Non-current trade receivables Concept (Monetary) As Of Debit ifrs-full:NoncurrentTradeReceivables
27 Other non-current assets Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentAssets
28 CURRENT ASSETS Concept (Monetary) As Of Debit ifrs-full:CurrentAssets
29 Trade and Other Receivables Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherCurrentReceivables
30 Other current assets Concept (Monetary) As Of Debit ifrs-full:OtherCurrentAssets
31 Short-term investments Concept (Monetary) As Of Debit ifrs-full:ShorttermInvestmentsClassifiedAsCashEquivalents
32 Cash and cash equivalents Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
33 TOTAL ASSETS Concept (Monetary) As Of Debit ifrs-full:Assets
34 EQUITY Concept (Monetary) As Of Credit ifrs-full:Equity
35 Share Capital Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
36 Share premium Concept (Monetary) As Of Credit ifrs-full:SharePremium
37 Other reserves Concept (Monetary) As Of Credit ifrs-full:OtherReserves
38 Retained loss Concept (Monetary) As Of Credit ifrs-full:RetainedEarnings
39 NON-CURRENT LIABILITIES Concept (Monetary) As Of Credit ifrs-full:NoncurrentLiabilities
40 Bank loans Concept (Monetary) As Of Credit ifrs-full:LongtermBorrowings
41 Finance leases Concept (Monetary) As Of Credit ifrs-full:NoncurrentFinanceLeaseLiabilities
42 Advances repayable Concept (Monetary) As Of Credit ifrs-full:NoncurrentAdvances
43 Contingent and other financial liabilities Concept (Monetary) As Of Credit cyad:ContingentConsiderationAndOtherFinancialLiabilities
44 Post employment benefits Concept (Monetary) As Of Credit ifrs-full:NoncurrentProvisionsForEmployeeBenefits
45 Other non-current liabilities Concept (Monetary) As Of Credit ifrs-full:OtherNoncurrentLiabilities
46 CURRENT LIABILITIES Concept (Monetary) As Of Credit ifrs-full:CurrentLiabilities
47 Bank loans Concept (Monetary) As Of Credit ifrs-full:ShorttermBorrowings
48 Finance leases Concept (Monetary) As Of Credit ifrs-full:CurrentFinanceLeaseLiabilities
49 Advances repayable Concept (Monetary) As Of Credit ifrs-full:CurrentAdvances
50 Trade payables Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherCurrentPayablesToTradeSuppliers
51 Other current liabilities Concept (Monetary) As Of Credit ifrs-full:OtherCurrentLiabilities
52 TOTAL EQUITY AND LIABILITIES Concept (Monetary) As Of Credit ifrs-full:EquityAndLiabilities
53 1004 - Statement - Consolidated Statements of Income (Loss) Network

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54 Implied Table Table

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55 Profit or loss [abstract] Abstract ifrs-full:IncomeStatementAbstract
56 Revenues Concept (Monetary) For Period Credit ifrs-full:Revenue
57 Cost of Sales Concept (Monetary) For Period Debit ifrs-full:CostOfSales
58 Gross profit Concept (Monetary) For Period Credit ifrs-full:GrossProfit
59 Research and Development expenses Concept (Monetary) For Period Debit ifrs-full:ResearchAndDevelopmentExpense
60 General and administrative expenses Concept (Monetary) For Period Debit ifrs-full:SellingGeneralAndAdministrativeExpense
61 Other income Concept (Monetary) For Period Credit ifrs-full:OtherIncome
62 Other expenses Concept (Monetary) For Period Debit cyad:OtherOperatingExpenses
63 Amendment of Celdara Medical and Dartmouth College agreements Concept (Monetary) For Period Debit cyad:ExpensesRelatedToAmendmentOfAgreements
64 Write-off C-Cure and Corquest assets and derecognition of related liabilities Concept (Monetary) For Period Debit cyad:WriteoffOfAssetsAndLiabilitiesOfCashGeneratingUnit
65 Operating Loss Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromOperatingActivities
66 Financial income Concept (Monetary) For Period Credit ifrs-full:FinanceIncome
67 Financial expenses Concept (Monetary) For Period Debit ifrs-full:FinanceCosts
68 Share of Loss of investment accounted for using the equity method Concept (Monetary) For Period Credit ifrs-full:ShareOfProfitLossOfAssociatesAndJointVenturesAccountedForUsingEquityMethod
69 Loss before taxes Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
70 Income Taxes Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
71 Loss for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
72 Weighted average number of shares outstanding Concept (Shares) For Period ifrs-full:WeightedAverageShares
73 Basic and diluted loss per share (in €) Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShare
74 1005 - Statement - Consolidated Statements of Comprehensive Income(Loss) Network

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75 Implied Table Table

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76 Statement of comprehensive income [abstract] Abstract ifrs-full:StatementOfComprehensiveIncomeAbstract
77 Loss for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
78 Other comprehensive income/(loss) Abstract ifrs-full:OtherComprehensiveIncomeAbstract
79 Items that will not be reclassified to profit and loss Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTax
80 Remeasurements of post employment benefit obligations, net of tax Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
81 Items that may be subsequently reclassified to profit or loss Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTax
82 Currency translation differences Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationNetOfTax
83 Other comprehensive income / (loss) for the year, net of tax Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
84 Total comprehensive gain/(loss) for the year Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
85 Total Comprehensive loss for the year attributable to Equity Holders Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncomeAttributableToOwnersOfParent
86 1006 - Statement - Consolidated Statements of Cash Flows Network

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87 Implied Table Table

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88 Statement of cash flows [abstract] Abstract ifrs-full:StatementOfCashFlowsAbstract
89 Cash Flow from operating activities Abstract ifrs-full:CashFlowsFromUsedInOperatingActivitiesAbstract
90 Loss for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
91 Non-cash adjustments Abstract ifrs-full:AdjustmentsForReconcileProfitLossAbstract
92 Intangibles-Amortisation & Impairment Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForAmortisationExpense
93 PP&E-Depreciation Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDepreciationExpense
94 Non-Cash expense for amendment of Celdara Medical and Dartmouth College agreements Concept (Monetary) For Period Debit cyad:AdjustmentsForAmendmentOfAgreements
95 Post-Employment Benefit Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForIncreaseDecreaseInEmployeeBenefitLiabilities
96 Deconsolidation of. CELYAD Asia Ltd. Concept (Monetary) For Period Debit cyad:AdjustmentsForIncreaseDecreaseInDeconsolidationOfBusiness
97 Change in fair value of Contingent consideration and other financial liabilities Concept (Monetary) For Period Debit cyad:AdjustmentsForDecreaseIncreaseInFairValueValuationOfContingentAndOtherFinancialLiabilities
98 Remeasurement of RCAs Concept (Monetary) For Period Credit cyad:AdjustmentsForIncreaseDecreaseInFairValueValuationOfRecoverableCashAdvances
99 RCAs and Grants income Concept (Monetary) For Period Credit cyad:AdjustmentsForProceedsOfGrantsAndAdvances
100 Currency Translation Adjustment Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForUnrealisedForeignExchangeLossesGains
101 Upfront payment settled in shares Concept (Monetary) For Period Credit cyad:UpfrontPaymentSettledInShares
102 Non-cash employee benefits expense - share based payments Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForSharebasedPayments
103 Change in working capital Abstract cyad:AdjustmentsForIncreaseDecreaseInWorkingCapitalAbstract
104 Trade receivables, other receivables, other non-current assets Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDecreaseIncreaseInTradeAndOtherReceivables
105 Trade payables, other payable and accruals Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForIncreaseDecreaseInTradeAndOtherPayables
106 Net cash used in operations Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperatingActivities
107 Cash Flow from investing activities Abstract ifrs-full:CashFlowsFromUsedInInvestingActivitiesAbstract
108 Acquisitions of Property, Plant & Equipment Concept (Monetary) For Period Credit ifrs-full:PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
109 Acquisitions of Intangible assets Concept (Monetary) For Period Credit ifrs-full:PurchaseOfIntangibleAssetsClassifiedAsInvestingActivities
110 Disposals of fixed assets Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalsOfPropertyPlantAndEquipmentIntangibleAssetsOtherThanGoodwillInvestmentPropertyAndOtherNoncurrentAssets
111 Contingent consideration pay out Concept (Monetary) For Period Credit cyad:PaymentOfContingentConsiderationPayOut
112 Acquisition of short term investments Concept (Monetary) For Period Credit ifrs-full:PurchaseOfInvestmentsOtherThanInvestmentsAccountedForUsingEquityMethod
113 Proceeds from short term investments Concept (Monetary) For Period Debit ifrs-full:ProceedsFromSalesOfInvestmentsOtherThanInvestmentsAccountedForUsingEquityMethod
114 Acquisition of BMS SA Concept (Monetary) For Period Credit ifrs-full:CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
115 Net cash (used in)/from investing activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInInvestingActivities
116 Cash Flow from financing activities Abstract ifrs-full:CashFlowsFromUsedInFinancingActivitiesAbstract
117 Proceeds from finance leases and bank borrowings Concept (Monetary) For Period Debit ifrs-full:ProceedsFromBorrowingsClassifiedAsFinancingActivities
118 Repayments of finance leases and bank borrowings Concept (Monetary) For Period Credit ifrs-full:PaymentsOfFinanceLeaseLiabilitiesClassifiedAsFinancingActivities
119 Proceeds from issuance of shares and exercise of warrants Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssuingShares
120 Proceeds from RCAs & other grants Concept (Monetary) For Period Debit ifrs-full:ProceedsFromGovernmentGrantsClassifiedAsFinancingActivities
121 Repayment of advances Concept (Monetary) For Period Credit ifrs-full:RepaymentsOfBorrowingsClassifiedAsFinancingActivities
122 Net cash (used in)/from financing activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInFinancingActivities
123 Net cash and cash equivalents at beginning of the period Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
124 Change in Cash and cash equivalents Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInCashAndCashEquivalents
125 Effects of exchange rate changes on cash and cash equivalents Concept (Monetary) For Period Debit ifrs-full:EffectOfExchangeRateChangesOnCashAndCashEquivalents
126 Net cash and cash equivalents at the end of the period Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
127 1007 - Statement - Consolidated Statement of Changes in Shareholders' Equity Network

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128 Statement of changes in equity [table] Table

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 ifrs-full:StatementOfChangesInEquityTable
129 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
130 Equity [member] Member ifrs-full:EquityMember
131 Share capital [member] Member ifrs-full:IssuedCapitalMember
132 Share premium [member] Member ifrs-full:SharePremiumMember
133 Other reserves [member] Member ifrs-full:OtherReservesMember
134 Accumulated Deficit [Member] Member ifrs-full:RetainedEarningsMember
135 Statement of changes in equity [line items] LineItems ifrs-full:StatementOfChangesInEquityLineItems
136 Beginning balance Concept (Monetary) As Of Credit ifrs-full:Equity
137 Capital increase in cash Concept (Monetary) For Period Debit cyad:IncreaseDecreaseThroughCapitalInvestment
138 Capital increase resulting from Celdara and Dartmouth College agreements amendment Concept (Monetary) For Period Credit ifrs-full:IssueOfEquity
139 Transaction costs associated with capital increases Concept (Monetary) For Period Credit cyad:IncreaseDecreaseThroughTransactionCostsAssociatedWithCapital
140 Exercise of warrants Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughExerciseOfWarrantsEquity
141 Share-based payments Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughSharebasedPaymentTransactions
142 Total transactions with owners, recognized directly in equity Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTransactionsWithOwners
143 Loss for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
144 Currency translation differences Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationNetOfTax
145 Remeasurements of defined benefit obligation Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
146 Total comprehensive gain/(loss) for the year Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
147 Ending balance Concept (Monetary) As Of Credit ifrs-full:Equity
148 1008 - Disclosure - The Company Network

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150 Text block [abstract] Abstract cyad:TextBlockAbstract
151 The Company Concept (Text Block (HTML)) For Period cyad:DisclosureOfGeneralBusinessDescriptionExplanatoryTextBlock
152 1009 - Disclosure - General information and Statement of Compliance Network

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154 Text block [abstract] Abstract cyad:TextBlockAbstract
155 General information and Statement of Compliance Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGeneralInformationAboutFinancialStatementsExplanatory
156 1010 - Disclosure - Accounting Principles Network

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157 Implied Table Table

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158 Text block [abstract] Abstract cyad:TextBlockAbstract
159 Accounting Principles Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSummaryOfSignificantAccountingPoliciesExplanatory
160 1011 - Disclosure - Risk Management Network

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162 Text block [abstract] Abstract cyad:TextBlockAbstract
163 Risk Management Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialRiskManagementExplanatory
164 1012 - Disclosure - Critical accounting estimates and judgments Network

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165 Implied Table Table

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166 Text block [abstract] Abstract cyad:TextBlockAbstract
167 Critical accounting estimates and judgments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfChangesInAccountingEstimatesExplanatory
168 1013 - Disclosure - Operating segment information Network

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169 Implied Table Table

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170 Text block [abstract] Abstract cyad:TextBlockAbstract
171 Operating segment information Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEntitysReportableSegmentsExplanatory
172 1014 - Disclosure - Intangible assets Network

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173 Implied Table Table

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174 Text block [abstract] Abstract cyad:TextBlockAbstract
175 Intangible assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIntangibleAssetsExplanatory
176 1015 - Disclosure - Property, plant and equipment Network

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177 Implied Table Table

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178 Text block [abstract] Abstract cyad:TextBlockAbstract
179 Property, plant and equipment Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfPropertyPlantAndEquipmentExplanatory
180 1016 - Disclosure - Other non-current assets Network

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181 Implied Table Table

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182 Text block [abstract] Abstract cyad:TextBlockAbstract
183 Other non-current assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherNoncurrentAssetsExplanatory
184 1017 - Disclosure - Inventories and Work in Progress Network

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186 Text block [abstract] Abstract cyad:TextBlockAbstract
187 Inventories and Work in Progress Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInventoriesExplanatory
188 1018 - Disclosure - Trade, Other Receivables and Other current assets Network

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189 Implied Table Table

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190 Text block [abstract] Abstract cyad:TextBlockAbstract
191 Trade, Other Receivables and Other current assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTradeAndOtherReceivablesExplanatory
192 1019 - Disclosure - Short Term Investments Network

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194 Text block [abstract] Abstract cyad:TextBlockAbstract
195 Short Term Investments Concept (Text Block (HTML)) For Period cyad:DisclosureOfShortTermInvestmentsExplanatory
196 1020 - Disclosure - Cash and Cash Equivalents Network

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197 Implied Table Table

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198 Text block [abstract] Abstract cyad:TextBlockAbstract
199 Cash and Cash Equivalents Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCashAndCashEquivalentsExplanatory
200 1021 - Disclosure - Investment in Subsidiaries Network

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201 Implied Table Table

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202 Text block [abstract] Abstract cyad:TextBlockAbstract
203 Investment in Subsidiaries Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfConsolidatedAndSeparateFinancialStatementsExplanatory
204 1022 - Disclosure - Share Capital Network

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205 Implied Table Table

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206 Text block [abstract] Abstract cyad:TextBlockAbstract
207 Share Capital Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfClassesOfShareCapitalExplanatory
208 1023 - Disclosure - Share-Based Payments Network

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210 Text block [abstract] Abstract cyad:TextBlockAbstract
211 Share-Based Payments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSharebasedPaymentArrangementsExplanatory
212 1024 - Disclosure - Post-Employment Benefits Network

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215 Post-Employment Benefits Concept (Text Block (HTML)) For Period cyad:DisclosurePostemploymentBenefitsExplanatory
216 1025 - Disclosure - Other Reserves Network

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217 Implied Table Table

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218 Text block [abstract] Abstract cyad:TextBlockAbstract
219 Other Reserves Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReservesAndOtherEquityInterestExplanatory
220 1026 - Disclosure - Advances Repayable Network

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223 Advances Repayable Concept (Text Block (HTML)) For Period cyad:DisclosureOfAdvancesRepayableExplanatory
224 1027 - Disclosure - Due Dates of the Financial Liabilities Network

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225 Implied Table Table

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227 Due Dates of the Financial Liabilities Concept (Text Block (HTML)) For Period cyad:DisclosureOfDueDatesOfFinancialLiabilitiesExplanatory
228 1028 - Disclosure - Trade Payables and Other Current Liabilities Network

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229 Implied Table Table

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231 Trade Payables and Other Current Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTradeAndOtherPayablesExplanatory
232 1029 - Disclosure - Financial Instruments on Balance Sheet Network

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235 Financial Instruments on Balance Sheet Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialInstrumentsExplanatory
236 1030 - Disclosure - Changes in Liabilities Arising from Financial Activities Network

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239 Changes in Liabilities Arising from Financial Activities Concept (Text Block (HTML)) For Period cyad:DisclosureOfSignificantFinancialTransactionWithRelatedPartiesExplanatory
240 1031 - Disclosure - Revenues and Net Other Income and Expenses Network

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243 Revenues and Net Other Income and Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfRevenueExplanatory
244 1032 - Disclosure - Operating Expenses Network

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245 Implied Table Table

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247 Operating Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfExpensesExplanatory
248 1033 - Disclosure - Employee Benefit Expenses Network

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251 Employee Benefit Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEmployeeBenefitsExplanatory
252 1034 - Disclosure - Financial Income and Expenses Network

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255 Financial Income and Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinanceIncomeExpenseExplanatory
256 1035 - Disclosure - Income Tax Network

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259 Income Tax Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIncomeTaxExplanatory
260 1036 - Disclosure - Deferred Taxes Network

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263 Deferred Taxes Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDeferredTaxesExplanatory
264 1037 - Disclosure - Commitments Network

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268 1038 - Disclosure - Relationships with Third-Parties Network

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270 Text block [abstract] Abstract cyad:TextBlockAbstract
271 Relationships with Third-Parties Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfRelatedPartyExplanatory
272 1039 - Disclosure - Loss per share Network

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273 Implied Table Table

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274 Text block [abstract] Abstract cyad:TextBlockAbstract
275 Loss per share Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEarningsPerShareExplanatory
276 1040 - Disclosure - Events after the close of the fiscal Year Network

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277 Implied Table Table

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278 Text block [abstract] Abstract cyad:TextBlockAbstract
279 Events after the close of the fiscal Year Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEventsAfterReportingPeriodExplanatory
280 1041 - Disclosure - Accounting Principles (Policies) Network

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281 Implied Table Table

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282 Text block [abstract] Abstract cyad:TextBlockAbstract
283 Subsidiaries Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForSubsidiariesExplanatory
284 Business Combinations Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForBusinessCombinationsExplanatory
285 Foreign currency translation Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory
286 Revenue Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForRecognitionOfRevenue
287 Licensing revenue Concept (Text Block (HTML)) For Period cyad:DescriptionOfAccountingPolicyForLicensingRevenueExplanatory
288 Government Grants (Other operating income) Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForGovernmentGrants
289 Intangible assets Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIntangibleAssetsOtherThanGoodwillExplanatory
290 Patents, Licences and Trademarks Concept (Text Block (HTML)) For Period cyad:DescriptionOfAccountingPolicyForPatentsLicensesAndTrademarksExplanatory
291 Software Concept (Text Block (HTML)) For Period cyad:DescriptionOfAccountingPolicyForComputerSoftwareExplanatory
292 Goodwill Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForGoodwillExplanatory
293 In process research and development costs Concept (Text Block (HTML)) For Period cyad:DescriptionOfAccountingPolicyForInProcessResearchAndDevelopmentCostsExplanatory
294 Research and development costs Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForResearchAndDevelopmentExpenseExplanatory
295 Property, plant and equipment Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory
296 Leases Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForLeasesExplanatory
297 Impairment of non-financial assets Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForImpairmentOfNonfinancialAssetsExplanatory
298 Cash and cash equivalents Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyToDetermineComponentsOfCashAndCashEquivalents
299 Financial assets Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForFinancialAssetsExplanatory
300 Financial liabilities Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForFinancialLiabilitiesExplanatory
301 Provisions Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForProvisionsExplanatory
302 Employee benefits Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForEmployeeBenefitsExplanatory
303 Income taxes Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIncomeTaxExplanatory
304 Deferred tax Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForDeferredIncomeTaxExplanatory
305 Earnings (loss) per share Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForEarningsPerShareExplanatory
306 1042 - Disclosure - General information and Statement of Compliance (Tables) Network

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307 Implied Table Table

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308 Text block [abstract] Abstract cyad:TextBlockAbstract
309 Summary of Implementation of New Standards on Gross Margin Previously Reported Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretations
310 1043 - Disclosure - Risk Management (Tables) Network

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311 Implied Table Table

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312 Text block [abstract] Abstract cyad:TextBlockAbstract
313 Foreign Exchange risk Exposure lied on Cash and Short-Term Deposits Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEffectOfChangesInForeignExchangeRatesExplanatory
314 1044 - Disclosure - Operating segment information (Tables) Network

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315 Implied Table Table

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316 Text block [abstract] Abstract cyad:TextBlockAbstract
317 Schedule of Segment Profit by Operating Segment Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOperatingSegmentsExplanatory
318 1045 - Disclosure - Intangible assets (Tables) Network

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319 Implied Table Table

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320 Text block [abstract] Abstract cyad:TextBlockAbstract
321 Summary of Intangible Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutIntangibleAssetsExplanatory
322 Summary of Probabilities of Success for Products Concept (Text Block (HTML)) For Period cyad:DisclosureOfProbabilitiesOfSuccessOfProductsExplanatory
323 Summary of Sensitivity Analyses of Recoverable Amount of CGU Concept (Text Block (HTML)) For Period cyad:DisclosureOfSensitivityAnalysisOfRecoverableAmountOfCGUExplanatory
324 1046 - Disclosure - Property, plant and equipment (Tables) Network

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325 Implied Table Table

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326 Text block [abstract] Abstract cyad:TextBlockAbstract
327 Summary of Changes in Carrying Value of Property, Plant and Equipment Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory
328 1047 - Disclosure - Other non-current assets (Tables) Network

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329 Implied Table Table

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330 Text block [abstract] Abstract cyad:TextBlockAbstract
331 Summary of Detailed Information About Non-current Trade Receivables Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutNoncurrentTradeReceivablesExplanatory
332 Summary of Other Non-current Assets Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutOtherNoncurrentAssetsExplanatory
333 1048 - Disclosure - Trade, Other Receivables and Other current assets (Tables) Network

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334 Implied Table Table

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335 Text block [abstract] Abstract cyad:TextBlockAbstract
336 Summary of Trade, Other Receivables and Other current assets Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutTradeAndOtherReceivablesExplanatory
337 1049 - Disclosure - Short Term Investments (Tables) Network

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338 Implied Table Table

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339 Text block [abstract] Abstract cyad:TextBlockAbstract
340 Summary of Short Term Investments Concept (Text Block (HTML)) For Period cyad:DisclosureDetailsOfShorttermInvestmentsExplanatory
341 1050 - Disclosure - Cash and Cash Equivalents (Tables) Network

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342 Implied Table Table

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343 Text block [abstract] Abstract cyad:TextBlockAbstract
344 Summary of Cash and Cash Equivalents Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationOfCashAndCashEquivalentsExplanatory
345 1051 - Disclosure - Investment in Subsidiaries (Tables) Network

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346 Implied Table Table

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347 Text block [abstract] Abstract cyad:TextBlockAbstract
348 Summary of Consolidated Subsidiaries Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesExplanatory
349 1052 - Disclosure - Share Capital (Tables) Network

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350 Implied Table Table

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351 Text block [abstract] Abstract cyad:TextBlockAbstract
352 Summary of Share Capital Issued Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIssuedCapitalExplanatory
353 Summary of Share Issuances Occurred Since the Incorporation of the Company Concept (Text Block (HTML)) For Period cyad:DisclosureOfShareIssuancesExplanatory
354 1053 - Disclosure - Share-Based Payments (Tables) Network

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355 Implied Table Table

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356 Text block [abstract] Abstract cyad:TextBlockAbstract
357 Changes in Number of Warrants Outstanding Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNumberAndWeightedAverageExercisePricesOfOtherEquityInstrumentsExplanatory
358 Summary of Warrants Outstanding Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementExplanatory
359 Summary of Fair Value of Warrants Determined At Grant Date Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIndirectMeasurementOfFairValueOfGoodsOrServicesReceivedOtherEquityInstrumentsGrantedDuringPeriodExplanatory
360 1054 - Disclosure - Post-Employment Benefits (Tables) Network

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361 Implied Table Table

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362 Text block [abstract] Abstract cyad:TextBlockAbstract
363 Summary of Pension Obligations Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDefinedBenefitPlansExplanatory
364 Summary of Defined Benefit Amounts Recognized in Balance Sheet Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
365 Summary of Change in Defined Benefit Liability Concept (Text Block (HTML)) For Period cyad:DisclosureOfMovementInDefinedBenefitLiabilityExplanatory
366 Summary of Income Statement Charge Included in Operating Profit for Post- employment Benefits Concept (Text Block (HTML)) For Period cyad:DisclosureOfIncomeStatementChargeIncludedInOperatingProfitForPostemploymentBenefitsExplanatory
367 Summary of Remeasurements Included in Other Comprehensive Loss Concept (Text Block (HTML)) For Period cyad:DisclosureOfRemeasurementsIncludedInOtherComprehensiveLossExplanatory
368 1055 - Disclosure - Other Reserves (Tables) Network

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369 Implied Table Table

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370 Text block [abstract] Abstract cyad:TextBlockAbstract
371 Summary of Information on Other Reserves Concept (Text Block (HTML)) For Period cyad:DisclosureOfInformationOnOtherReservesExplanatory
372 1056 - Disclosure - Advances Repayable (Tables) Network

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373 Implied Table Table

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374 Text block [abstract] Abstract cyad:TextBlockAbstract
375 Summary of Current and Non-current Portion Financial Liabilities Concept (Text Block (HTML)) For Period cyad:DisclosureOfCurrentAndNonCurrentFinancialLiabilitiesExplanatory
376 Summary of Information on Other Outstanding Advances Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutOtherOutstandingAdvancesExplanatory
377 Summary of Certain Terms and Conditions for the Recoverable Cash Advances Concept (Text Block (HTML)) For Period cyad:DisclosureOfCertainTermsAndConditionsForTheRecoverableCashAdvancesExplanatory
378 1057 - Disclosure - Due Dates of the Financial Liabilities (Tables) Network

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379 Implied Table Table

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380 Text block [abstract] Abstract cyad:TextBlockAbstract
381 Aggregate Information Material Contractual Obligations and Payments Due Concept (Text Block (HTML)) For Period ifrs-full:MaturityAnalysisForNonderivativeFinancialLiabilities
382 1058 - Disclosure - Trade Payables and Other Current Liabilities (Tables) Network

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383 Implied Table Table

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384 Text block [abstract] Abstract cyad:TextBlockAbstract
385 Trade Payables and Other Current Liabilities Concept (Text Block (HTML)) For Period cyad:DisclosureOfTradeAndOtherCurrentPayablesExplanatory
386 1059 - Disclosure - Financial Instruments on Balance Sheet (Tables) Network

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387 Implied Table Table

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388 Text block [abstract] Abstract cyad:TextBlockAbstract
389 Summary of Carrying and Fair Values of Financial Instruments that are not Carried at Fair Value Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutFinancialInstrumentsExplanatory
390 Schedule of Financial Assets and Liabilities Measured at Fair Value Concept (Text Block (HTML)) For Period cyad:DisclosureOfFinancialAssetsAndLiabilitiesByMeasurementBasisExplanatory
391 Contingent Consideration and Other Financial Liabilities Concept (Text Block (HTML)) For Period cyad:DisclosureOfContingentConsiderationAndOtherFinancialLiabilitiesExplanatory
392 Sensitivity Analysis Performed on Main Assumptions Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutSensitivityToChangesInAssumptionsExplanatory
393 1060 - Disclosure - Changes in Liabilities Arising from Financial Activities (Tables) Network

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394 Implied Table Table

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395 Text block [abstract] Abstract cyad:TextBlockAbstract
396 Summary of Bank Loans Financial Liability Roll Forward Concept (Text Block (HTML)) For Period cyad:DisclosureOfBankLoansFinancialLiabilityRollForwardTextBlock
397 Summary of Finance Leases Financial Liability Roll Forward Concept (Text Block (HTML)) For Period cyad:DisclosureOfFinanceLeasesFinancialLiabilityRollForwardExplanatory
398 Summary of Recoverable Cash Advance Liability Roll Forward Concept (Text Block (HTML)) For Period cyad:DisclosureOfRecoverableCashAdvanceLiabilityRollForwardExplanatory
399 1061 - Disclosure - Revenues and Net Other Income and Expenses (Tables) Network

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400 Implied Table Table

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401 Text block [abstract] Abstract cyad:TextBlockAbstract
402 Summary of Revenues Concept (Text Block (HTML)) For Period cyad:DisclosureOfOperatingRevenueExplanatory
403 Summary of Other Operating Income and Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherOperatingIncomeExpenseExplanatory
404 1062 - Disclosure - Operating Expenses (Tables) Network

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405 Implied Table Table

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406 Text block [abstract] Abstract cyad:TextBlockAbstract
407 Summary of Research and Development Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfResearchAndDevelopmentExpenseExplanatory
408 Summary of General and Administrative Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGeneralAndAdministrativeExpenseExplanatory
409 Summary of Non-recurring Operating Income and Expenses Concept (Text Block (HTML)) For Period cyad:DisclosureOfNonRecurringOperatingIncomeAndExpenses
410 1063 - Disclosure - Employee Benefit Expenses (Tables) Network

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411 Implied Table Table

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412 Text block [abstract] Abstract cyad:TextBlockAbstract
413 Summary of Employee Expenses Concept (Text Block (HTML)) For Period cyad:DisclosureOfEmployeeBenefitExpensesExplanatory
414 1064 - Disclosure - Financial Income and Expenses (Tables) Network

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415 Implied Table Table

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416 Text block [abstract] Abstract cyad:TextBlockAbstract
417 Sunmmary of Financial Revenues and Expenses Concept (Text Block (HTML)) For Period cyad:DisclosureOfDetailedInformationAboutFinanceIncomeExpenseExplanatory
418 1065 - Disclosure - Income Tax (Tables) Network

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419 Implied Table Table

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420 Text block [abstract] Abstract cyad:TextBlockAbstract
421 Summary of Group Reports Income Taxes in the Income Statement Concept (Text Block (HTML)) For Period cyad:DisclosureOfComponentsOfTaxExpenseIncome
422 Schedule of Reconciliation Between Effective and Theoretical Tax Concept (Text Block (HTML)) For Period cyad:DisclosureOfReconciliationOfIncomeTaxExpenseBenefitExplanatory
423 1066 - Disclosure - Deferred Taxes (Tables) Network

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424 Implied Table Table

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425 Text block [abstract] Abstract cyad:TextBlockAbstract
426 Schedule of Unrecognized Deferred Tax Assets and Liabilities Concept (Text Block (HTML)) For Period cyad:DisclosureOfDeferredTaxAssetsAndLiabilitiesExplanatory
427 Schedule of Unrecognised Deferred Tax Asset Balance Roll Forward Concept (Text Block (HTML)) For Period cyad:DisclosureOfUnrecognizedDeferredTaxAssetsExplanatory
428 1067 - Disclosure - Relationships with Third-Parties (Tables) Network

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429 Implied Table Table

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430 Text block [abstract] Abstract cyad:TextBlockAbstract
431 Summary of Remuneration of Key Management Informations Concept (Text Block (HTML)) For Period cyad:DisclosureOfKeyManagementPersonnelCompensationExplanatory
432 Summary of Transactions with Related Parties Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesExplanatory
433 1068 - Disclosure - Loss per share (Tables) Network

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434 Implied Table Table

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435 Text block [abstract] Abstract cyad:TextBlockAbstract
436 Calculation of Earnings (Loss) Per Share Concept (Text Block (HTML)) For Period ifrs-full:EarningsPerShareExplanatory
437 1069 - Disclosure - The Company - Additional Information (Detail) Network

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438 Implied Table Table

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439 Disclosure of detailed information about business combination [abstract] Abstract ifrs-full:DisclosureOfBusinessCombinationsAbstract
440 Number of subsidiaries owned by the entity Concept (Integer) For Period cyad:NumberOfSubsidiaries
441 1070 - Disclosure - General Information and Statement of Compliance - Summary of Implementation of New Standards on Gross Margin Previously Reported (Detail) Network

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442 Disclosure of expected impact of initial application of new standards or interpretations [table] Table

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443 Retrospective application and retrospective restatement [axis] Axis ifrs-full:RetrospectiveApplicationAndRetrospectiveRestatementAxis
444 Currently stated [member] Member ifrs-full:RestatedMember
445 Previously stated [member] Member ifrs-full:PreviouslyStatedMember
446 Increase (decrease) due to application of IFRS 15 [member] Member ifrs-full:IncreaseDecreaseDueToApplicationOfIFRS15Member
447 Disclosure of expected impact of initial application of new standards or interpretations [line items] LineItems ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems
448 Licensing revenue Concept (Monetary) For Period Credit cyad:GrossRevenueFromLicensing
449 Cost of licensing Concept (Monetary) For Period Debit cyad:CostOfLicensing
450 Gross Profit Concept (Monetary) For Period Credit ifrs-full:GrossProfit
451 1071 - Disclosure - General Information and Statement of Compliance - Additional Information (Detail) Network

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452 Disclosure of expected impact of initial application of new standards or interpretations [table] Table

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453 Non-adjusting events after reporting period [axis] Axis ifrs-full:NonadjustingEventsAfterReportingPeriodAxis
454 Non-adjusting events after reporting period [member] Member ifrs-full:NonadjustingEventsMember
455 Announcing or commencing implementation of major restructuring [member] Member ifrs-full:AnnouncingOrCommencingImplementationOfMajorRestructuringMember
456 Retrospective application and retrospective restatement [axis] Axis ifrs-full:RetrospectiveApplicationAndRetrospectiveRestatementAxis
457 Currently stated [member] Member ifrs-full:RestatedMember
458 IFRS 16 [member] Member cyad:IFRS16Member
459 Disclosure of expected impact of initial application of new standards or interpretations [line items] LineItems ifrs-full:DescriptionOfExpectedImpactOfInitialApplicationOfNewStandardsOrInterpretationsLineItems
460 Lease liability Concept (Monetary) As Of Credit ifrs-full:LeaseLiabilities
461 1072 - Disclosure - Accounting Principles - Additional Information (Detail) Network

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462 Disclosure of significant accounting policies [table] Table

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463 Range [axis] Axis ifrs-full:RangeAxis
464 Ranges [member] Member ifrs-full:RangesMember
465 Top of range [member] Member ifrs-full:TopOfRangeMember
466 Bottom of range [member] Member ifrs-full:BottomOfRangeMember
467 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
468 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
469 Land and buildings [member] Member ifrs-full:LandAndBuildingsMember
470 Plant and equipment [member] Member cyad:PlantAndEquipmentMember
471 Laboratory equipment [member] Member cyad:LaboratoryEquipmentMember
472 Furniture [member] Member cyad:FurnitureMember
473 Leasehold improvements [member] Member ifrs-full:LeaseholdImprovementsMember
474 Classes of intangible assets and goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
475 Intangible assets and goodwill [member] Member ifrs-full:IntangibleAssetsAndGoodwillMember
476 Software [member] Member ifrs-full:ComputerSoftwareMember
477 Disclosure of significant accounting policies [line items] LineItems cyad:DisclosureOfSignificantAccountingPoliciesLineItems
478 Exploitation phase period for recoverable cash advances Concept (xbrli:durationItemType) For Period cyad:ExploitationPhasePeriodForRecoverableCashAdvances
479 Estimated useful lives of software Concept (Text/String) For Period ifrs-full:UsefulLivesOrAmortisationRatesIntangibleAssetsOtherThanGoodwill
480 Development costs, capitalization period Concept (xbrli:durationItemType) For Period cyad:DevelopmentCostsCapitalizationPeriod
481 Development costs, amortization period Concept (xbrli:durationItemType) For Period cyad:DevelopmentCostsAmortizationPeriod
482 Depreciation on property, plant and equipment Concept (Text/String) For Period ifrs-full:UsefulLivesOrDepreciationRatesPropertyPlantAndEquipment
483 Number of cash generating units Concept (Integer) For Period cyad:NumberOfCashGeneratingUnits
484 Cash and cash equivalents, original maturity period Concept (xbrli:durationItemType) For Period cyad:CashAndCashEquivalentsOriginalMaturityPeriod
485 Non-current financial assets, description Concept (Text/String) For Period cyad:NoncurrentFinancialAssetsDescription
486 1073 - Disclosure - Risk management - Summary of Foreign Exchange Risk (Detail) Network

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487 Disclosure of nature and extent of risks arising from financial instruments [table] Table

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488 Statement scenario [axis] Axis cyad:StatementScenarioAxis
489 Statement scenario [member] Member cyad:StatementScenarioMember
490 A2 Percentage Depreciation [member] Member cyad:A2PercentageDepreciationMember
491 A1 Percentage Depreciation [member] Member cyad:A1PercentageDepreciationMember
492 A1 Percentage Appreciation [member] Member cyad:A1PercentageAppreciationMember
493 A2 Percentage Appreciation [member] Member cyad:A2PercentageAppreciationMember
494 Disclosure of nature and extent of risks arising from financial instruments [line items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
495 Unrealized foreign (loss) gain Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationBeforeTax
496 1074 - Disclosure - Risk Management - Additional information (Detail) Network

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497 Disclosure of nature and extent of risks arising from financial instruments [table] Table

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498 Statement scenario [axis] Axis cyad:StatementScenarioAxis
499 Statement scenario [member] Member cyad:StatementScenarioMember
500 A1 Percentage Depreciation [member] Member cyad:A1PercentageDepreciationMember
501 Disclosure of nature and extent of risks arising from financial instruments [line items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
502 Unrealized foreign (loss) gain Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationBeforeTax
503 1075 - Disclosure - Critical Accounting Estimates and Judgments - Additional Information (Detail) Network

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504 Implied Table Table

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505 Disclosure of changes in accounting estimates [abstract] Abstract ifrs-full:DisclosureOfChangesInAccountingEstimatesAbstract
506 Repayable recoverable cash advances percentage Concept (Percent) For Period cyad:RepayableRecoverableCashAdvancesPercentage
507 1076 - Disclosure - Operating Segment Information - Additional Information (Detail) Network

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508 Disclosure of operating segments [table] Table

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509 Segments [axis] Axis ifrs-full:SegmentsAxis
510 Segments [member] Member ifrs-full:SegmentsMember
511 Cathez [member] Member cyad:CathezMember
512 Cardiology [member] Member cyad:CardiologyMember
513 Type of arrangement 1 [axis] Axis cyad:TypeOfArrangement1Axis
514 Type of arrangement [member] Member cyad:TypeOfArrangementMember
515 Mesoblast licence agreement [member] Member cyad:MesoblastLicenceAgreementMember
516 Disclosure of operating segments [line items] LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
517 Number of operating segments Concept (Integer) For Period cyad:NumberOfOperatingSegments1
518 Revenue from sales Concept (Monetary) For Period Credit cyad:RevenueArisingFromExchangesOfGoodsOrServicesSaleOfGoods1
519 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
520 1077 - Disclosure - Operating Segment Information - Schedule of Segment Profit by Operating Segment (Detail) Network

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521 Disclosure of operating segments [table] Table

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 ifrs-full:DisclosureOfOperatingSegmentsTable
522 Segments [axis] Axis ifrs-full:SegmentsAxis
523 Segments [member] Member ifrs-full:SegmentsMember
524 Cardiology [member] Member cyad:CardiologyMember
525 Immuno-oncology [member] Member cyad:ImmunoOncologyMember
526 Corporate [member] Member cyad:CorporateMember
527 Disclosure of operating segments [line items] LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
528 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
529 Cost of Sales Concept (Monetary) For Period Debit ifrs-full:CostOfSales
530 Gross Profit Concept (Monetary) For Period Credit ifrs-full:GrossProfit
531 Research & Development expenses Concept (Monetary) For Period Debit ifrs-full:ResearchAndDevelopmentExpense
532 General & Administrative expenses Concept (Monetary) For Period Debit ifrs-full:SellingGeneralAndAdministrativeExpense
533 Other Income and expenses Concept (Monetary) For Period Credit ifrs-full:OtherOperatingIncomeExpense
534 Recurring operating profit (Loss)-REBIT Concept (Monetary) For Period Credit cyad:RecurringOperatingIncomeAndExpenses
535 Non-recurring operating (expenses)/income Concept (Monetary) For Period Credit cyad:NonrecurringOperatingIncomeAndExpenses
536 Operating Loss Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromOperatingActivities
537 Net Financial Charges Concept (Monetary) For Period Credit ifrs-full:FinanceIncomeCost
538 Loss before taxes Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
539 Income Taxes Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
540 Profit (Loss) for the year Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
541 1078 - Disclosure - Intangible Assets - Summary of Intangible Assets (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureIntangibleAssetsSummaryOfIntangibleAssets
542 Disclosure of detailed information about intangible assets [table] Table

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 ifrs-full:DisclosureOfIntangibleAssetsTable
543 Classes of intangible assets and goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
544 Intangible assets and goodwill [member] Member ifrs-full:IntangibleAssetsAndGoodwillMember
545 Goodwill [member] Member ifrs-full:GoodwillMember
546 In-process research and development [member] Member ifrs-full:IntangibleAssetsUnderDevelopmentMember
547 Development cost [member] Member cyad:DevelopmentCostMember
548 Patents, licences, trademarks [member] Member ifrs-full:CopyrightsPatentsAndOtherIndustrialPropertyRightsServiceAndOperatingRightsMember
549 Software [member] Member ifrs-full:ComputerSoftwareMember
550 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
551 Carrying amount [member] Member ifrs-full:CarryingAmountMember
552 Cost [member] Member ifrs-full:GrossCarryingAmountMember
553 Accumulated depreciation and amortisation [member] Member ifrs-full:AccumulatedDepreciationAndAmortisationMember
554 Disclosure of detailed information about intangible assets [line items] LineItems ifrs-full:DisclosureOfIntangibleAssetsLineItems
555 Beginning balance Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
556 Additions Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill
557 Amortisation charge Concept (Monetary) For Period ifrs-full:AmortisationIntangibleAssetsOtherThanGoodwill
558 Currency translation adjustments Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesIntangibleAssetsAndGoodwill
559 Divestiture Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesIntangibleAssetsAndGoodwill
560 Impairment (non-recurring loss) Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill
561 Ending balance Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsAndGoodwill
562 1079 - Disclosure - Intangible Assets - Additional Information (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureIntangibleAssetsAdditionalInformation
563 Disclosure of detailed information about intangible assets [table] Table

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*

 ifrs-full:DisclosureOfIntangibleAssetsTable
564 Range [axis] Axis ifrs-full:RangeAxis
565 Ranges [member] Member ifrs-full:RangesMember
566 Bottom of range [member] Member ifrs-full:BottomOfRangeMember
567 Top of range [member] Member ifrs-full:TopOfRangeMember
568 Classes of intangible assets and goodwill [axis] Axis ifrs-full:ClassesOfIntangibleAssetsAndGoodwillAxis
569 Intangible assets and goodwill [member] Member ifrs-full:IntangibleAssetsAndGoodwillMember
570 Software [member] Member ifrs-full:ComputerSoftwareMember
571 Licences [member] Member ifrs-full:LicencesMember
572 Patents 1 [member] Member cyad:Patents1Member
573 Products and services [axis] Axis ifrs-full:ProductsAndServicesAxis
574 Products and services [member] Member ifrs-full:ProductsAndServicesMember
575 C-Cure [member] Member cyad:CCureProductsMember
576 HeartXs assets [member] Member cyad:HeartXsAssetsMember
577 Individual assets or cash-generating units [axis] Axis ifrs-full:IndividualAssetsOrCashgeneratingUnitsAxis
578 Entity's total for individual assets or cash-generating units [member] Member ifrs-full:EntitysTotalForIndividualAssetsOrCashgeneratingUnitsMember
579 CorQuest LLC [member] Member cyad:CorQuestLLCMember
580 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
581 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
582 CorQuest LLC [member] Member cyad:CorQuestLLCMember
583 Type of arrangement 1 [axis] Axis cyad:TypeOfArrangement1Axis
584 Type of arrangement [member] Member cyad:TypeOfArrangementMember
585 Horizon discovery agreement [member] Member cyad:HorizonDiscoveryAgreementMember
586 Disclosure of detailed information about intangible assets [line items] LineItems ifrs-full:DisclosureOfIntangibleAssetsLineItems
587 Intangible asset amortization period Concept (Text/String) For Period ifrs-full:UsefulLivesOrAmortisationRatesIntangibleAssetsOtherThanGoodwill
588 Intangible assets Concept (Monetary) As Of Debit ifrs-full:IntangibleAssetsOtherThanGoodwill
589 Impairment loss on intangible assets Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsOtherThanGoodwill
590 Fair value of intellectual rights assets Concept (Monetary) As Of Debit cyad:FairValueOfIntellectualRightsAssets
591 CAR-T Therapies acquired Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsIntangibleAssetsOtherThanGoodwill
592 Intellectual property protection period Concept (Text/String) For Period cyad:IntellectualPropertyProtectionPeriod
593 Description of key assumptions Concept (Text/String) For Period ifrs-full:DescriptionOfKeyAssumptionsOnWhichManagementHasBasedCashFlowProjections
594 Period over which management has projected cash flows Concept (Text/String) For Period ifrs-full:ExplanationOfPeriodOverWhichManagementHasProjectedCashFlows
595 Impairment loss on intangible assets and goodwill Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossIntangibleAssetsAndGoodwill
596 Description of discount rate assumptions Concept (Text/String) For Period cyad:DescriptionOfDiscountRateAssumptions
597 Sales revenue growth rate Concept (Percent) As Of ifrs-full:DescriptionOfGrowthRateUsedToExtrapolateCashFlowProjections
598 Percentage of impairment allowances carry forward Concept (Percent) As Of cyad:PercentageOfImpairmentAllowancesCarryForward
599 1080 - Disclosure - Intangible Assets - Summary of Probabilities of Success for Products (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureIntangibleAssetsSummaryOfProbabilitiesOfSuccessForProducts
600 Disclosure of detailed information about intangible assets [table] Table

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*

 ifrs-full:DisclosureOfIntangibleAssetsTable
601 Measurement [axis] Axis ifrs-full:MeasurementAxis
602 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
603 Phase I [member] Member cyad:PhaseOneMember
604 Phase I to II [member] Member cyad:PhaseOneToTwoMember
605 Phase II to III [member] Member cyad:PhaseTwoToThreeMember
606 Phase III to BLA [member] Member cyad:PhaseThreeToBLAMember
607 BLA to approval [member] Member cyad:BLAToApprovalMember
608 Products and services [axis] Axis ifrs-full:ProductsAndServicesAxis
609 Products and services [member] Member ifrs-full:ProductsAndServicesMember
610 CYAD 01 [member] Member cyad:Cyad01Member
611 Disclosure of detailed information about intangible assets [line items] LineItems ifrs-full:DisclosureOfIntangibleAssetsLineItems
612 Probablity of success percentage Concept (Percent) For Period cyad:ProbabilityOfSuccessPercentage
613 1081 - Disclosure - Intangible Assets - Summary of Sensitivity Analyses of Recoverable Amount of CGU (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureIntangibleAssetsSummaryOfSensitivityAnalysesOfRecoverableAmountOfCGU
614 Disclosure of detailed information about intangible assets [table] Table

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*

 ifrs-full:DisclosureOfIntangibleAssetsTable
615 Valuation techniques used in fair value measurement [axis] Axis ifrs-full:ValuationTechniquesUsedInFairValueMeasurementAxis
616 Valuation techniques [member] Member ifrs-full:ValuationTechniquesMember
617 Discount rate at 13.90% [member] Member cyad:DiscountRateAtThirteenPointNineZeroPercentageMember
618 Discount rate at 14.65% [member] Member cyad:DiscountRateAtFourteenPointSixFivePercentageMember
619 Discount rate at 15.40% [member] Member cyad:DiscountRateAtFifteenPointFourZeroPercentageMember
620 Measurement [axis] Axis ifrs-full:MeasurementAxis
621 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
622 Impact of -35% [member] Member cyad:ImpactOfMinusThirtyFivePercentageMember
623 Impact of -30% [member] Member cyad:ImpactOfMinusThirtyPercentageMember
624 Impact of -25% [member] Member cyad:ImpactOfMinusTwentyFivePercentageMember
625 Disclosure of detailed information about intangible assets [line items] LineItems ifrs-full:DisclosureOfIntangibleAssetsLineItems
626 Terminal Revenue Growth rate Concept (Percent) For Period cyad:TerminalRevenueGrowthRatePercentage
627 1082 - Disclosure - Property, Plant and Equipment - Summary of Changes in Carrying Value of Property, Plant and Equipment (Detail) Network

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628 Disclosure of detailed information about property, plant and equipment [table] Table

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 ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
629 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
630 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
631 Equipment [Member] Member ifrs-full:MachineryMember
632 Furniture [member] Member cyad:FurnitureMember
633 Leasehold improvements [member] Member ifrs-full:LeaseholdImprovementsMember
634 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
635 Carrying amount [member] Member ifrs-full:CarryingAmountMember
636 Cost [member] Member ifrs-full:GrossCarryingAmountMember
637 Accumulated depreciation [Member] Member ifrs-full:AccumulatedDepreciationAmortisationAndImpairmentMember
638 Disclosure of detailed information about property, plant and equipment [line items] LineItems ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
639 Beginning balance Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
640 Additions Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
641 Reclass BMS SA Concept (Monetary) For Period Credit cyad:ReclassificationAdjustmentsOfPropertyPlantAndEquipment
642 Depreciation charge (note 5.25) Concept (Monetary) For Period ifrs-full:DepreciationPropertyPlantAndEquipment
643 Acquisition of BMS SA Concept (Monetary) For Period Debit ifrs-full:AcquisitionsThroughBusinessCombinationsPropertyPlantAndEquipment
644 Disposals Concept (Monetary) For Period Credit ifrs-full:DisposalsPropertyPlantAndEquipment
645 Currency translation adjustments Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughNetExchangeDifferencesPropertyPlantAndEquipment
646 Ending balance Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
647 1083 - Disclosure - Property, Plant and Equipment - Additional Information (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosurePropertyPlantAndEquipmentAdditionalInformation
648 Implied Table Table

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 implied:Table
649 Disclosure of detailed information about property, plant and equipment [abstract] Abstract ifrs-full:DisclosureOfPropertyPlantAndEquipmentAbstract
650 Finance leases maturity term Concept (xbrli:durationItemType) For Period cyad:FinanceLeasesMaturityPeriod
651 1084 - Disclosure - Other Non-current Assets - Summary of Detailed Information About Non-current Trade Receivables (Detail) Network

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652 Disclosure of other non-current assets [table] Table

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 cyad:DisclosureOfOtherNoncurrentAssetsTable
653 Type of arrangement 1 [axis] Axis cyad:TypeOfArrangement1Axis
654 Type of arrangement [member] Member cyad:TypeOfArrangementMember
655 Mesoblast licence agreement [member] Member cyad:MesoblastLicenceAgreementMember
656 Disclosure of other non current assets [line items] LineItems cyad:DisclosureOfOtherNonCurrentAssetsLineItems
657 Non-current trade receivables Mesoblast licence agreement Concept (Monetary) As Of Debit ifrs-full:NoncurrentReceivables
658 1085 - Disclosure - Other Non-current Assets - Summary of Non-current Financial Assets (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureOtherNoncurrentAssetsSummaryOfNoncurrentFinancialAssets
659 Implied Table Table

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660 Disclosure of Other Noncurrent Assets [abstract] Abstract cyad:DisclosureOfOtherNoncurrentAssetsAbstract
661 Deposits Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentFinancialAssets
662 R&D Tax credit receivable Concept (Monetary) As Of Debit cyad:ResearchAndDevelopmentTaxCreditReceivableNonCurrent
663 Total Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentAssets
664 1086 - Disclosure - Other Non-current Assets - Additional Information (Detail) Network

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665 Implied Table Table

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666 Disclosure of Other Noncurrent Assets [abstract] Abstract cyad:DisclosureOfOtherNoncurrentAssetsAbstract
667 R&D Tax credit receivable Concept (Monetary) As Of Debit cyad:ResearchAndDevelopmentTaxCreditReceivableNonCurrent
668 R&D Tax credit receivable increase (decrease) Concept (Monetary) For Period Debit cyad:IncreaseDecreaseResearchAndDevelopmentTaxCreditReceivableNonCurrent
669 1087 - Disclosure - Trade, Other Receivables and Other current assets - Summary of Trade Receivables and Other Current Assets (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureTradeOtherReceivablesAndOtherCurrentAssetsSummaryOfTradeReceivablesAndOtherCurrentAssets
670 Implied Table Table

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671 Disclosure of trade and other receivables [abstract] Abstract cyad:DisclosureOfTradeAndOtherReceivablesAbstract
672 Trade receivables Concept (Monetary) As Of Debit ifrs-full:CurrentTradeReceivables
673 Advance deposits Concept (Monetary) As Of Debit cyad:CurrentAdvanceDeposits
674 Other trade receivables Concept (Monetary) As Of Debit cyad:OtherTradeCurrentReceivables
675 Total Trade and Other receivables Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherCurrentReceivables
676 Prepaid expenses Concept (Monetary) As Of Debit ifrs-full:CurrentPrepaidExpenses
677 VAT receivable Concept (Monetary) As Of Debit ifrs-full:CurrentValueAddedTaxReceivables
678 Income and other tax receivables Concept (Monetary) As Of Debit ifrs-full:ReceivablesFromTaxesOtherThanIncomeTax
679 Total Other current assets Concept (Monetary) As Of Debit ifrs-full:OtherCurrentAssets
680 1088 - Disclosure - Trade, Other Receivables and Other Current Assets - Additional Information (Detail) Network

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*

 http://www.celyad.com/taxonomy/role/DisclosureTradeOtherReceivablesAndOtherCurrentAssetsAdditionalInformation
681 Disclosure of trade and other receivables [table] Table

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 cyad:DisclosureOfTradeAndOtherReceivablesTable
682 Currency [Axis] Axis srt:CurrencyAxis
683 All Currencies [Domain] Member currency:AllCurrenciesDomain
684 Foreign currencies [member] Member cyad:ForeignCurrenciesMember
685 Products and services [axis] Axis ifrs-full:ProductsAndServicesAxis
686 Products and services [member] Member ifrs-full:ProductsAndServicesMember
687 Ono non clinical supply services agreement [member] Member cyad:OnoNonClinicalSupplyServicesAgreementMember
688 Disclosure of trade and other receivables [line items] LineItems cyad:DisclosureOfTradeAndOtherReceivablesLineItems
689 Trade and other receivables overdue Concept (Monetary) As Of Debit cyad:TradeAndOtherReceivablesOverdue
690 Carrying amounts for trade and other receivables denominated in foreign currencies Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherReceivables
691 Impairment loss Concept (Monetary) For Period Debit ifrs-full:ImpairmentLossRecognisedInProfitOrLossTradeReceivables
692 Increase in Trade receivables Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDecreaseIncreaseInTradeAccountReceivable
693 1089 - Disclosure - Short Term Investments - Summary of Short Term Investments (Detail) Network

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694 Implied Table Table

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695 Short term investments1 [abstract] Abstract cyad:ShortTermInvestments1Abstract
696 Short-term cash deposits Concept (Monetary) As Of Debit ifrs-full:ShorttermDepositsClassifiedAsCashEquivalents
697 Investment in equity securities Concept (Monetary) As Of Debit ifrs-full:InvestmentAccountedForUsingEquityMethod
698 Total Concept (Monetary) As Of Debit ifrs-full:CurrentInvestments
699 1090 - Disclosure - Cash and Cash Equivalents - Summary of Cash and Cash Equivalents (Detail) Network

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*

 http://www.celyad.com/taxonomy/role/DisclosureCashAndCashEquivalentsSummaryOfCashAndCashEquivalents
700 Implied Table Table

*

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701 Cash and cash equivalents [abstract] Abstract ifrs-full:CashAndCashEquivalentsAbstract
702 Cash at bank and on hand Concept (Monetary) As Of Debit ifrs-full:Cash
703 Total Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
704 1091 - Disclosure - Investment in Subsidiaries - Summary of Consolidated Subsidiaries (Detail) Network

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*

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705 Disclosure of subsidiaries [table] Table

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*

 ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesTable
706 Subsidiaries [axis] Axis ifrs-full:SignificantInvestmentsInSubsidiariesAxis
707 Entity's total for subsidiaries [member] Member ifrs-full:EntitysTotalForSubsidiariesMember
708 Celyad Inc [member] Member cyad:CelyadIncMember
709 Oncyte LLC Member cyad:OncyteLLCMember
710 Corquest Medical Inc [member] Member cyad:CorquestMedicalIncMember
711 Biological Manufacturing Services SA [member] Member cyad:BiologicalManufacturingServicesSAMember
712 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
713 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
714 USA [member] Member country:US
715 Belgium [member] Member country:BE
716 Disclosure of subsidiaries [line items] LineItems ifrs-full:DisclosureOfSignificantInvestmentsInSubsidiariesLineItems
717 Name Concept (Text/String) For Period ifrs-full:NameOfSubsidiary
718 Country of Incorporation and Place of Business Concept (Text/String) For Period ifrs-full:CountryOfIncorporationOrResidenceOfSubsidiary
719 Nature of Business Concept (Text/String) For Period cyad:DescriptionOfPrimaryBusinessOfSubsidiary
720 Proportion of Propo ordinary ordina shares directly held by held by parent (%) Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestInSubsidiary
721 Proportion of ordinary shares held by the group (%) Concept (Percent) For Period cyad:ProportionOfOwnershipInterestsHeldByGroup
722 Proportion of ordinary shares held by non-controlling interests (%) Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestsHeldByNoncontrollingInterests
723 1092 - Disclosure - Share Capital Issued - Summary of Share Capital Issued (Detail) Network

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*

 http://www.celyad.com/taxonomy/role/DisclosureShareCapitalIssuedSummaryOfShareCapitalIssued
724 Implied Table Table

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*

 implied:Table
725 Disclosure of classes of share capital [abstract] Abstract ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
726 Total number of issued and outstanding shares Concept (Shares) As Of cyad:CommonSharesIssuedAndOutstanding
727 Total share capital Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
728 1093 - Disclosure - Share Capital Issued - Additional Information (Detail) Network

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*

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729 Disclosure of classes of share capital [table] Table

*

*

 ifrs-full:DisclosureOfClassesOfShareCapitalTable
730 Classes of share capital [axis] Axis ifrs-full:ClassesOfShareCapitalAxis
731 Share capital [member] Member ifrs-full:ClassesOfShareCapitalMember
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733 Class B shares [member] Member cyad:ClassBSharesMember
734 Class B shares [member] Member cyad:ClassBSharesTwoMember
735 Warrant A [member] Member cyad:WarrantAMember
736 Counterparties [axis] Axis ifrs-full:CounterpartiesAxis
737 Counterparties [member] Member ifrs-full:CounterpartiesMember
738 Mayo Clinic [member] Member cyad:MayoClinicMember
739 Medisun International Limited [member] Member cyad:MedisunInternationalLimitedMember
740 Categories of related parties [axis] Axis ifrs-full:CategoriesOfRelatedPartiesAxis
741 Entity's total for related parties [member] Member ifrs-full:EntitysTotalForRelatedPartiesMember
742 Round B Investors [member] Member cyad:RoundBInvestorsMember
743 Existing investor [member] Member cyad:ExistingInvestorMember
744 New Investor [member] Member cyad:NewInvestorMember
745 Round C Investors [member] Member cyad:RoundCInvestorsMember
746 Celdara Medical [member] Member cyad:CeldaraMedicalMember
747 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
748 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
749 Conversion of Loan D [member] Member cyad:LoanDMember
750 Conversion of Loan C [member] Member cyad:LoanCMember
751 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
752 Assets [member] Member ifrs-full:ClassesOfAssetsMember
753 Convertible loan [member] Member cyad:ConvertibleLoanMember
754 Cash 1 [member] Member cyad:Cash1Member
755 Uncalled Cash [member] Member cyad:UncalledCashMember
756 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
757 Equity [member] Member ifrs-full:EquityMember
758 Initial public offering [member] Member cyad:InitialPublicOfferingMember
759 Over allotment option [member] Member cyad:OverAllotmentOption1Member
760 Share capital [member] Member ifrs-full:IssuedCapitalMember
761 Share premium [member] Member ifrs-full:SharePremiumMember
762 Private placement [member] Member cyad:PrivatePlacementsMember
763 Other reserves [member] Member ifrs-full:OtherReservesMember
764 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
765 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
766 Oncyte LLC Member cyad:OncyteLLCMember
767 Disclosure of classes of share capital [line items] LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
768 Issued capital Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
769 Number of ordinary shares Concept (Shares) As Of ifrs-full:NumberOfSharesIssuedAndFullyPaid
770 Common stock , par value Concept (Share) As Of ifrs-full:ParValuePerShare
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774 Contribution in kind of the upfront fee that was due upon execution of the Mayo Licence Concept (Monetary) For Period ifrs-full:TransfersUnderLicenseAgreementsFromEntityRelatedPartyTransactions
775 Capital contribution Concept (Monetary) For Period ifrs-full:TransfersUnderFinanceAgreementsToEntityRelatedPartyTransactions
776 Shares authorized Concept (Shares) As Of ifrs-full:NumberOfSharesAuthorised
777 Proceeds from capital increase Concept (Monetary) For Period Debit cyad:ProceedsFromCapitalIncreaseClassifiedAsFinancingActivities
778 Warrants exercised Concept (Shares) As Of cyad:WarrantsExercised
779 Proceeds from exercise of warrants Concept (Monetary) For Period Debit cyad:ProceedsFromExerciseOfWarrants
780 Warrants exercise price Concept (Share) For Period cyad:WarrantExercisePrice
781 Share conversion price per share Concept (Share) For Period cyad:ShareConversionPricePerShare
782 Nominal amount Concept (Monetary) As Of ifrs-full:NotionalAmount
783 Contribution in kind Concept (Monetary) For Period ifrs-full:TransfersOfResearchAndDevelopmentFromEntityRelatedPartyTransactions
784 Increase in capital Concept (Monetary) For Period cyad:IncreaseDecreaseInCapital
785 Convertible loans converted to shares, amount Concept (Monetary) For Period Debit cyad:ConvertibleLoansConvertedToSharesAmount
786 Increase in capital and issue premium by contribution in cash Concept (Monetary) For Period Credit cyad:IncreaseInCapitalAndIssuePremiumByContributionInCash
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788 Proceeds from issuing shares Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssuingShares
789 Cost related to capital increase Concept (Monetary) For Period Debit cyad:CostRelatedToCapitalIncrease
790 Description of authorization invested in board of directors Concept (Text/String) For Period cyad:DescriptionOfAuthorizationInvestedInBoardOfDirectors
791 Expected increase in capital Concept (Monetary) For Period cyad:ExpectedIncreaseDecreaseInCapital
792 Shares subscribed Concept (Shares) As Of cyad:NumberOfSharesSubscribed
793 Shares issued related to exercise of warrants Concept (Shares) For Period cyad:NumberOfSharesIssuedRelatedToExerciseOfWarrants
794 Warrants exercise periods Concept (Text/String) For Period cyad:WarrantsExercisePeriod
795 Description of share price calculation Concept (Text/String) For Period cyad:DescriptionOfSharePriceCalculation
796 Issue Of Equity Concept (Monetary) For Period Credit ifrs-full:IssueOfEquity
797 Number of shares issued and outstanding Concept (Shares) As Of cyad:NumberOfSharesIssuedAndOutstanding
798 1094 - Disclosure - Share Capital Issued - Summary of Share Issuances Occurred Since the Incorporation of the Company (Detail) Network

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799 Disclosure of classes of share capital [table] Table

*

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 ifrs-full:DisclosureOfClassesOfShareCapitalTable
800 Classes of share capital [axis] Axis ifrs-full:ClassesOfShareCapitalAxis
801 Share capital [member] Member ifrs-full:ClassesOfShareCapitalMember
802 Class A shares [member] Member cyad:ClassASharesOneMember
803 Class A shares [member] Member cyad:ClassASharesTwoMember
804 Class B shares [member] Member cyad:ClassBSharesOneMember
805 Class B shares [member] Member cyad:ClassBSharesTwoMember
806 Class B shares [member] Member cyad:ClassBSharesThreeMember
807 Class B shares [member] Member cyad:ClassBSharesFourMember
808 Class B shares [member] Member cyad:ClassBSharesFiveMember
809 Class B shares [member] Member cyad:ClassBSharesSixMember
810 Class B shares [member] Member cyad:ClassBSharesSevenMember
811 Class B shares [member] Member cyad:ClassBSharesEightMember
812 Class B shares [member] Member cyad:ClassBSharesNineMember
813 Class B shares [member] Member cyad:ClassBSharesTenMember
814 Class B shares [member] Member cyad:ClassBSharesElevenMember
815 Class B shares [member] Member cyad:ClassBSharesTwelveMember
816 Class B shares [member] Member cyad:ClassBSharesThirteenMember
817 Class B shares [member] Member cyad:ClassBSharesFourteenMember
818 Class B shares [member] Member cyad:ClassBSharesFifteenMember
819 Ordinary shares [member] Member cyad:OrdinarySharesOneMember
820 Ordinary shares [member] Member cyad:OrdinarySharesTwoMember
821 Ordinary shares [member] Member cyad:OrdinarySharesThreeMember
822 Ordinary shares [member] Member cyad:OrdinarySharesFourMember
823 Ordinary shares [member] Member cyad:OrdinarySharesFiveMember
824 Ordinary shares [member] Member cyad:OrdinarySharesSixMember
825 Ordinary shares [member] Member cyad:OrdinarySharesSevenMember
826 Ordinary shares [member] Member cyad:OrdinarySharesEightMember
827 Ordinary shares [member] Member cyad:OrdinarySharesNineMember
828 Ordinary shares [member] Member cyad:OrdinarySharesTenMember
829 Ordinary shares [member] Member cyad:OrdinarySharesElevenMember
830 Ordinary shares [member] Member cyad:OrdinarySharesTwelveMember
831 Ordinary shares [member] Member cyad:OrdinarySharesThirteenMember
832 Ordinary shares [member] Member cyad:OrdinarySharesFourteenMember
833 Ordinary shares [member] Member cyad:OrdinarySharesFifteenMember
834 Ordinary shares [member] Member cyad:OrdinarySharesSixteenMember
835 Ordinary shares [member] Member cyad:OrdinarySharesSeventeenMember
836 Ordinary shares [member] Member cyad:OrdinarySharesEighteenMember
837 Ordinary shares [member] Member cyad:OrdinarySharesNineteenMember
838 Ordinary shares twenty [member] Member cyad:OrdinarySharesTwentyMember
839 Ordinary shares twenty one [member] Member cyad:OrdinarySharesTwentyOneMember
840 Ordinary shares twenty two [member] Member cyad:OrdinarySharesTwentyTwoMember
841 Ordinary shares twenty three [member] Member cyad:OrdinarySharesTwentyThreeMember
842 Ordinary shares twenty four [member] Member cyad:OrdinarySharesTwentyFourMember
843 Ordinary shares twenty five [member] Member cyad:OrdinarySharesTwentyFiveMember
844 Ordinary shares twenty six [member] Member cyad:OrdinarySharesTwentySixMember
845 Ordinary shares twenty seven [member] Member cyad:OrdinarySharesTwentySevenMember
846 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
847 Equity [member] Member ifrs-full:EquityMember
848 Share capital [member] Member ifrs-full:IssuedCapitalMember
849 Share premium [member] Member ifrs-full:SharePremiumMember
850 Number of shares [member] Member cyad:NumberOfSharesMember
851 Disclosure of classes of share capital [line items] LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
852 Transaction date Concept (Date) For Period cyad:ShareIssuanceTransactionDate
853 Description Concept (Text/String) For Period cyad:DescriptionOfShareissuanceTransaction
854 # of shares Concept (Shares) As Of ifrs-full:NumberOfSharesIssued
855 Par value Concept (Share) As Of ifrs-full:ParValuePerShare
856 Beginning balance Concept (Monetary) As Of Credit ifrs-full:Equity
857 Issue of shares related to exercise of warrants Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughExerciseOfWarrantsEquity
858 Capital increase resulting from Celdara and Dartmouth College agreements amendment Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughExerciseOfOptions
859 Capital increase as a result of the global offering Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssueOfOrdinaryShares
860 Share-based payments Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughSharebasedPaymentTransactions
861 Ending balance Concept (Monetary) As Of Credit ifrs-full:Equity
862 1095 - Disclosure - Share-based Payments - Changes in Number of Warrants Outstanding (Detail) Network

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863 Implied Table Table

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864 Disclosure of terms and conditions of share-based payment arrangement [abstract] Abstract ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract
865 Weighted average exercise price, outstanding, beginning of period Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
866 Weighted average exercise price, granted Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsGrantedInSharebasedPaymentArrangement
867 Weighted average exercise price, forfeited Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
868 Weighted average exercise price, exercised Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
869 Weighted average exercise price, expired Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsExpiredInSharebasedPaymentArrangement
870 Weighted average exercise price outstanding, end of period Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
871 Number of warrants outstanding, beginning of period Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
872 Number of warrants, granted Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
873 Number of warrants, forfeited Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
874 Number of warrants, exercised Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
875 Number of warrants, expired Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExpiredInSharebasedPaymentArrangement
876 Number of warrants outstanding, end of period Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
877 1096 - Disclosure - Share-based Payments - Additional Information (Detail) Network

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878 Disclosure of terms and conditions of share-based payment arrangement [table] Table

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 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
879 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
880 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
881 Warrant1 [member] Member cyad:Warrant1Member
882 Warrants plan issuance date 5 November 2015 [member] Member cyad:WarrantsPlanIssuanceDateFiveNovemberTwoThousandFifteenMember
883 Range [axis] Axis ifrs-full:RangeAxis
884 Ranges [member] Member ifrs-full:RangesMember
885 Bottom of range [member] Member ifrs-full:BottomOfRangeMember
886 Top of range [member] Member ifrs-full:TopOfRangeMember
887 Disclosure of terms and conditions of share-based payment arrangement [line items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
888 Number of warrant exercised Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
889 New issue of warrants Concept (Decimal) For Period cyad:NumberOfOtherEquityInstrumentsIssuedInSharebasedPaymentArrangement
890 Number of warrants authorized Concept (Shares) For Period cyad:NumberOfOtherEquityInstrumentsAuthorisedToGrantInShareBasedPaymentArrangement
891 Number of warrants offered Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
892 Number of warrants outstanding Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
893 Warrants expiration date Concept (xbrli:durationItemType) For Period cyad:WarrantsExpirationPeriod
894 Percentage of warrants vested Concept (Percent) For Period cyad:WarrantsVestingRightsPercentage
895 Exercise price of the different tranches ranges Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
896 Warrants exercise period Concept (Text/String) For Period cyad:WarrantsExercisePeriod
897 Number of tranches Concept (Integer) For Period cyad:NumberOfTranches
898 Number of warrants cancelled Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
899 Net expense recognized Concept (Monetary) For Period Debit cyad:ShareBasedPaymentExpense
900 1097 - Disclosure - Share-based Payments - Summary of Warrants Outstanding (Detail) Network

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901 Disclosure of terms and conditions of share-based payment arrangement [table] Table

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*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
902 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
903 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
904 29 Oct 2010 [member] Member cyad:WarrantsGrantDateTwentyNineOctoberTwoThousandTenMember
905 26 October 2018 [member] Member cyad:WarrantsGrantDateTwentySixOctoberTwoThousandEighteenMember
906 06 May 2013 [member] Member cyad:WarrantsGrantDateSixMayTwoThousandThirteenMember
907 05 May 2014 [member] Member cyad:WarrantsGrantDateFiveMayTwoThousandFourteenMember
908 05 November 2015 [member] Member cyad:WarrantsGrantDateFiveNovemberTwoThousandFifteenMember
909 08 December 2016 [member] Member cyad:WarrantsGrantDateEightDecemberTwoThousandSixteenMember
910 29 June 2017 [member] Member cyad:WarrantsGrantDateTwentyNineJuneTwoThousandSeventeenMember
911 Disclosure of terms and conditions of share-based payment arrangement [line items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
912 Warrant plan issuance date Concept (Text/String) For Period ifrs-full:DateOfGrantOfSharebasedPaymentArrangement
913 Vesting date Concept (Text/String) For Period cyad:VestingDateOfSharebasedPaymentArrangement
914 Expiry date Concept (Text/String) For Period cyad:ExpiryDateOfSharebasedPaymentArrangement
915 Number of warrants outstanding as of 31 December, Ex 2016 Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
916 Exercise price per share Concept (Share) As Of cyad:ExercisePriceOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
917 1098 - Disclosure - Share-based Payments - Summary of Fair Value of Warrants Determined At Grant Date (Detail) Network

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918 Disclosure of terms and conditions of share-based payment arrangement [table] Table

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919 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
920 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
921 Warrant issued 2016 [Member] Member cyad:WarrantsGrantDateDecemberTwoThousandSixteenMember
922 29 June 2017 [member] Member cyad:WarrantsGrantDateTwentyNineJuneTwoThousandSeventeenMember
923 05 May 2010 (warrants B) [member] Member cyad:WarrantsbGrantDateFiveMayTwoThousandTenMember
924 05 May 2010 (warrants C) [member] Member cyad:WarrantscGrantDateFiveMayTwoThousandTenMember
925 29 Oct 2010 [member] Member cyad:WarrantsGrantDateTwentyNineOctoberTwoThousandTenMember
926 05 May 2014 [member] Member cyad:WarrantsGrantDateFiveMayTwoThousandFourteenMember
927 05 November 2015 [member] Member cyad:WarrantsGrantDateFiveNovemberTwoThousandFifteenMember
928 Actuarial assumptions [axis] Axis ifrs-full:ActuarialAssumptionsAxis
929 Actuarial assumptions [member] Member ifrs-full:ActuarialAssumptionsMember
930 Black-Scholes Pricing Model [Member] Member cyad:BlackScholesPricingModelMember
931 Disclosure of terms and conditions of share-based payment arrangement [line items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
932 Number of warrants issued Concept (Decimal) For Period cyad:NumberOfOtherEquityInstrumentsIssuedInSharebasedPaymentArrangement
933 Number of warrants granted Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
934 Number of warrants not fully vested as of 31 December 2017 Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
935 Average exercise price Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfOtherEquityInstrumentsExercisableInSharebasedPaymentArrangement
936 Expected share value volatility Concept (Percent) For Period cyad:FairValueAssumptionsExpectedVolatilityRate1
937 Risk-free interest rate Concept (Percent) For Period cyad:FairValueAssumptionsRiskFreeInterestRate1
938 Average fair value Concept (Monetary) As Of cyad:WeightedAverageFairValueAtOtherEquityInstrumentsOutstanding
939 Weighted average remaining contractual life Concept (xbrli:durationItemType) For Period cyad:WeightedAverageRemainingContractualLifeOfWarrants
940 1099 - Disclosure - Post Employment Benefits - Summary of Pension Obligations (Detail) Network

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941 Implied Table Table

*

*

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942 Disclosure of defined benefit plans [abstract] Abstract ifrs-full:DisclosureOfDefinedBenefitPlansAbstract
943 Pension obligations Concept (Monetary) As Of Credit ifrs-full:NoncurrentProvisionsForEmployeeBenefits
944 Total Concept (Monetary) As Of Credit ifrs-full:NoncurrentProvisions
945 1100 - Disclosure - Post Employment Benefits - Additional Information (Detail) Network

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946 Implied Table Table

*

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 implied:Table
947 Disclosure of net defined benefit liability (asset) [abstract] Abstract ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetAbstract
948 Employee contributions Concept (Monetary) For Period Credit ifrs-full:EmployeeContributions
949 Mortality rate for men Concept (Decimal) For Period cyad:MortalityRateForMen
950 Mortality rate for women Concept (Decimal) For Period cyad:MortalityRateForWomen
951 Actuarial assumption of withdrawal rate each year Concept (Percent) As Of cyad:ActuarialAssumptionOfWithdrawalRates
952 Actuarial assumption of retirement age Concept (Decimal) As Of ifrs-full:ActuarialAssumptionOfRetirementAge
953 Yearly inflation rate Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfExpectedRatesOfInflation
954 Actuarial assumption of yearly salary raise above inflation Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
955 Actuarial assumption of yearly discount rates Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfDiscountRates
956 Percentage of reasonably possible increase decrease in actuarial assumption description Concept (Text/String) For Period cyad:DescriptionOfPercentageOfReasonablyPossibleIncreaseDecreaseInActuarialAssumption
957 Expected contributions to pension benefit plans Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedContributionPlans
958 1101 - Disclosure - Post Employment Benefits - Summary of Defined Benefit Amounts Recognized in Balance Sheet (Detail) Network

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959 Implied Table Table

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960 Disclosure of net defined benefit liability (asset) [abstract] Abstract ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetAbstract
961 Present value of funded obligations Concept (Monetary) As Of Credit ifrs-full:DefinedBenefitObligationAtPresentValue
962 Fair value of plan assets Concept (Monetary) As Of Debit ifrs-full:PlanAssetsAtFairValue
963 Deficit of funded plans Concept (Monetary) As Of Credit cyad:DeficitInPlan
964 Total deficit of defined benefit pension plans Concept (Monetary) As Of Debit ifrs-full:SurplusDeficitInPlan
965 Liability in the balance sheet Concept (Monetary) As Of Credit ifrs-full:NoncurrentProvisionsForEmployeeBenefits
966 1102 - Disclosure - Post Employment Benefits - Summary of Change in Defined Benefit Liability (Detail) Network

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967 Disclosure of net defined benefit liability (asset) [table] Table

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 ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetTable
968 Net defined benefit liability (asset) [axis] Axis ifrs-full:NetDefinedBenefitLiabilityAssetAxis
969 Net defined benefit liability (asset) [member] Member ifrs-full:NetDefinedBenefitLiabilityAssetMember
970 Present value of obligation [member] Member ifrs-full:PresentValueOfDefinedBenefitObligationMember
971 Fair value of plan assets [member] Member ifrs-full:PlanAssetsMember
972 Disclosure of net defined benefit liability (asset) [line items] LineItems ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetLineItems
973 Beginning balance Concept (Monetary) As Of Credit ifrs-full:LiabilityAssetOfDefinedBenefitPlans
974 Current service cost Concept (Monetary) For Period Credit ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
975 Interest expense/(income) Concept (Monetary) For Period Credit ifrs-full:InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
976 Increase (decrease) in net defined benefit liability (asset) Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseInNetDefinedBenefitLiabilityAsset
977 Remeasurements Abstract ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAssetAbstract
978 - Return on plan assets, excluding amounts included in interest expense/(income) Concept (Monetary) For Period Debit ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
979 - Actuarial (Gain)/loss due to change in actuarial assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
980 - Actuarial (Gain)/Loss due to experience Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset
981 Remeasurement of post-employment benefit obligation Concept (Monetary) For Period Debit ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAsset
982 Employer contributions: Concept (Monetary) For Period Debit ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
983 Benefits Paid Concept (Monetary) For Period Debit ifrs-full:ContributionsToPlanNetDefinedBenefitLiabilityAsset
984 Ending balance Concept (Monetary) As Of Credit ifrs-full:LiabilityAssetOfDefinedBenefitPlans
985 1103 - Disclosure - Post Employment Benefits - Summary of Income Statement Charge Included in Operating Profit for Post- employment Benefits (Detail) Network

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986 Implied Table Table

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987 Disclosure of net defined benefit liability (asset) [abstract] Abstract ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetAbstract
988 Current service cost Concept (Monetary) For Period Credit ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
989 Interest expense on DBO Concept (Monetary) For Period Credit cyad:DefinedBenefitObligationInterestExpenseOnObligation
990 Expected return on plan assets Concept (Monetary) For Period Credit cyad:InterestIncomeOnPlanAssets
991 Net periodic pension cost Concept (Monetary) For Period Credit cyad:DefinedBenefitObligationCostOfNetProfitLoss
992 1104 - Disclosure - Post Employment Benefits - Summary of Re-measurements Included in Other Comprehensive Loss (Detail) Network

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993 Implied Table Table

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994 Disclosure of net defined benefit liability (asset) [abstract] Abstract ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetAbstract
995 Effect of changes in actuarial assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
996 Effect of experience adjustments Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset
997 (Gain)/Loss on assets for the year Concept (Monetary) For Period Debit ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
998 Remeasurement of post-employment benefit obligations Concept (Monetary) For Period Debit ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAsset
999 1105 - Disclosure - Other Reserves - Summary of Information on Other Reserves (Detail) Network

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1000 DisclosureOf Information On Other Reserves [table] Table

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 cyad:DisclosureofInformationOnOtherReservesTable
1001 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
1002 Equity [member] Member ifrs-full:EquityMember
1003 Share based payment reserve [member] Member ifrs-full:ReserveOfSharebasedPaymentsMember
1004 Convertible loan [member] Member ifrs-full:ReserveOfEquityComponentOfConvertibleInstrumentsMember
1005 Translation [member] Member ifrs-full:ReserveOfExchangeDifferencesOnTranslationMember
1006 Disclosure of information on other reserves [Line Items] LineItems cyad:DisclosureOfInformationOnOtherReservesLineItems
1007 Other reserves beginning balance Concept (Monetary) As Of Credit ifrs-full:OtherReserves
1008 Vested share-based payments Concept (Monetary) For Period Credit cyad:ReserveOfVestedShareBasedPayments
1009 Currency Translation differences subsidiaries Concept (Monetary) For Period Credit cyad:ReserveForCurrencyTranslationDifferencesSubsidiaries
1010 Other reserves ending balance Concept (Monetary) As Of Credit ifrs-full:OtherReserves
1011 1106 - Disclosure - Advances repayable - Summary of Current and Non-current Portion Financial Liabilities (Detail) Network

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1012 Implied Table Table

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1013 Disclosure of financial liabilities [abstract] Abstract ifrs-full:DisclosureOfFinancialLiabilitiesAbstract
1014 Total Non-Current portion as at 1st January Concept (Monetary) As Of Credit ifrs-full:NoncurrentAdvances
1015 Total Non-Current portion as at 31 December Concept (Monetary) As Of Credit ifrs-full:NoncurrentAdvances
1016 Total Current portion as at 1st January Concept (Monetary) As Of Credit ifrs-full:CurrentAdvances
1017 Total Current portion as at 31 December Concept (Monetary) As Of Credit ifrs-full:CurrentAdvances
1018 1107 - Disclosure - Advances Repayable - Additional Information (Detail) Network

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1019 Disclosure of financial liabilities [table] Table

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1020 Types of contracts [axis] Axis ifrs-full:TypesOfContractsAxis
1021 Types of contracts [member] Member ifrs-full:TypesOfContractsMember
1022 5915 [member] Member cyad:FiveNineOneFiveContractNumberMember
1023 Other contracts [member] Member cyad:OtherContractsMember
1024 Range [axis] Axis ifrs-full:RangeAxis
1025 Ranges [member] Member ifrs-full:RangesMember
1026 Bottom of range [member] Member ifrs-full:BottomOfRangeMember
1027 Top of range [member] Member ifrs-full:TopOfRangeMember
1028 Disclosure of financial liabilities [line items] LineItems ifrs-full:DisclosureOfFinancialLiabilitiesLineItems
1029 Contracted recoverable cash advances Concept (Monetary) As Of Credit cyad:ContractualAmount
1030 Recoverable cash advances banked Concept (Monetary) As Of Credit cyad:RecoverableCashAdvancesBanked
1031 Existing contracts amounts Concept (Monetary) As Of Debit cyad:ContractualAmountYetToReceived
1032 Contractual amount Concept (Monetary) As Of Credit cyad:RecoverableCashAdvancesRelatedToContractsForExploitationHasBeenAbandoned
1033 Percentage of budgeted project cost Concept (Percent) For Period cyad:PercentageOfBudgetedProjectCosts
1034 Payment equivalent percentage of price received Concept (Percent) For Period cyad:PaymentEquivalentPercentageOfPriceReceived
1035 Payment equivalent percentage of price received Concept (Percent) For Period cyad:SaleIndependentDependentReimbursementsAndAmountDueInCaseOfOutLicensingAgreementOrSaleToThirdPartyEquivalentPercentageOfPrincipalAmount
1036 Sales independent reimbursements equivalent percentage of principal amount Concept (Percent) For Period cyad:SalesIndependentReimbursementsEquivalentPercentageOfPrincipalAmount
1037 Sales independent reimbursements percentage Concept (Percent) For Period cyad:SalesIndependentReimbursementsPercentage
1038 1108 - Disclosure - Advances repayable - Summary of Information on Other Outstanding Advances (Detail) Network

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1039 Disclosure of financial liabilities [table] Table

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1040 Types of contracts [axis] Axis ifrs-full:TypesOfContractsAxis
1041 Types of contracts [member] Member ifrs-full:TypesOfContractsMember
1042 5160 [member] Member cyad:FiveOneSixZeroContractNumberMember
1043 5731 [member] Member cyad:FiveSevenThreeOneContractNumberMember
1044 5914 [member] Member cyad:FiveNineOneFourContractNumberMember
1045 5915 [member] Member cyad:FiveNineOneFiveContractNumberMember
1046 5951 [member] Member cyad:FiveNineFiveOneContractNumberMember
1047 6003 [member] Member cyad:SixZeroZeroThreeContractNumberMember
1048 6230 [member] Member cyad:SixTwoThreeZeroContractNumberMember
1049 6363 [member] Member cyad:SixThreeSixThreeContractNumberMember
1050 6548 [member] Member cyad:SixFiveFourEightContractNumberMember
1051 6633 [member] Member cyad:SixSixThreeThreeContractNumberMember
1052 6646 [member] Member cyad:SixSixFourSixContractNumberMember
1053 7027 [member] Member cyad:SevenZeroTwoSevenContractNumberMember
1054 7246 [member] Member cyad:SevenTwoFourSixContractNumberMember
1055 7502 [member] Member cyad:SevenFiveZeroTwoContractNumberMember
1056 7685 [member] Member cyad:SevenSixEightFiveContractNumberMember
1057 Disclosure of financial liabilities [line items] LineItems ifrs-full:DisclosureOfFinancialLiabilitiesLineItems
1058 Project Concept (Text/String) For Period cyad:ProjectDescription
1059 Amounts received prior years Concept (Monetary) As Of Credit cyad:RecoverableCashAdvancesReceivedInPreviousYears
1060 Amounts received, Previous years Concept (Monetary) As Of Credit cyad:ContractualAmount
1061 Amounts received Concept (Monetary) As Of Credit cyad:RecoverableCashAdvancesReceived
1062 Amounts received Cumulated cashed in Concept (Monetary) As Of Credit cyad:RecoverableCashAdvances
1063 To receive in 2018 and beyond Concept (Monetary) As Of Debit cyad:ContractualAmountYetToReceived
1064 Status Concept (Text/String) For Period cyad:DescriptionOfContractStatus
1065 Amount reimbursed (cumulative) Concept (Monetary) As Of Credit cyad:ContractualAmountReimbursed
1066 1109 - Disclosure - Advances repayable - Certain Terms and Conditions for Recoverable Cash Advances (Detail) Network

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1067 Disclosure of financial liabilities [table] Table

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1068 Types of contracts [axis] Axis ifrs-full:TypesOfContractsAxis
1069 Types of contracts [member] Member ifrs-full:TypesOfContractsMember
1070 5160 [member] Member cyad:FiveOneSixZeroContractNumberMember
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1350 Other benefit expense Concept (Monetary) For Period Debit ifrs-full:OtherEmployeeExpense
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1352 1127 - Disclosure - Employee Benefit Expenses - Additional Information (Detail) Network

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1353 Implied Table Table

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1354 Disclosure of employee benefits expenses [abstract] Abstract cyad:DisclosureOfEmployeeBenefitsExpensesAbstract
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1356 1128 - Disclosure - Financial Income and Expenses - Summary of Financial Revenues and Expenses (Detail) Network

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1357 Implied Table Table

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1360 Interest on overdrafts and other finance costs Concept (Monetary) For Period Debit ifrs-full:InterestExpenseOnBankLoansAndOverdrafts
1361 Interest on RCAs Concept (Monetary) For Period Debit cyad:InterestExpenseOnRecoverableCashAdvances
1362 Foreign Exchange differences Concept (Monetary) For Period Debit cyad:ExpensesDueToExchangeDifferences
1363 Finance expenses Concept (Monetary) For Period Debit ifrs-full:FinanceCosts
1364 Interest income bank account Concept (Monetary) For Period Credit ifrs-full:InterestIncomeOnDeposits
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1367 Finance income Concept (Monetary) For Period Credit ifrs-full:FinanceIncome
1368 Net Financial result Concept (Monetary) For Period Credit ifrs-full:FinanceIncomeCost
1369 1129 - Disclosure - Income Tax expense - Summary of Group Reports Income Taxes in the Income Statement (Detail) Network

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1370 Implied Table Table

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1373 Deferred tax (expense) / income Concept (Monetary) For Period Debit ifrs-full:DeferredTaxExpenseIncome
1374 Total income tax (expense) / income in profit or loss Concept (Monetary) For Period cyad:CurrentAndDeferredTaxExpenseIncomeRecognisedInProfitOrLoss
1375 1130 - Disclosure - Income Tax - Additional Information (Detail) Network

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1376 Implied Table Table

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1377 Major components of tax expense (income) [abstract] Abstract ifrs-full:MajorComponentsOfTaxExpenseIncomeAbstract
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1379 1131 - Disclosure - Income Tax - Schedule of Reconciliation Between Effective And Theoretical Income Tax (Detail) Network

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 http://www.celyad.com/taxonomy/role/DisclosureIncomeTaxScheduleOfReconciliationBetweenEffectiveAndTheoreticalIncomeTax
1380 Implied Table Table

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1388 Effective tax expense Concept (Monetary) For Period Credit cyad:EffectiveTaxRateProfitBeforeIncomeTaxes
1389 Effective tax rate Concept (Percent) For Period ifrs-full:AverageEffectiveTaxRate
1390 1132 - Disclosure - Deferred Taxes - Schedule of Unrecognized Deferred Tax Assets and Liabilities (Detail) Network

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1391 Disclosure of Deferred Tax Assets And Liabilities [table] Table

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1394 RCA's [member] Member cyad:RecoverableCashAdvancesMember
1395 Employee benefits liability [member] Member cyad:EmployeeBenefitsLiabilityMember
1396 Other temporary differences [member] Member ifrs-full:OtherTemporaryDifferencesMember
1397 Tax Losses Carry forward [member] Member cyad:TaxLossesCarryForwardMember
1398 Classes of contingent liabilities [axis] Axis ifrs-full:ClassesOfContingentLiabilitiesAxis
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1405 Deferred tax asset [member] Member cyad:DeferredTaxAssetMember
1406 Deferred tax liabilities [member] Member cyad:DeferredTaxLiabilitiesMember
1407 Disclosure of Deferred Tax Assets And Liabilities [line items] LineItems cyad:DisclosureOfDeferredTaxAssetsAndLiabilitiesLineItems
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1410 Unrecognized deferred tax assets and liabilities, net Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilityAsset
1411 Unrecognised Gross Deferred Tax assets/(liabilities) Concept (Monetary) For Period Debit cyad:UnrecognizedDeferredTaxAssetsAndLiabilitiesGross
1412 Netting by tax entity Concept (Monetary) For Period Credit cyad:UnrecognizedDeferredTaxAssetsAndLiabilitiesNettingByTaxEntity
1413 Unrecognised Net Deferred Tax assets/(liabilities) Concept (Monetary) For Period Debit cyad:UnrecognizedDeferredTaxAssetsAndLiabilitiesNet
1414 1133 - Disclosure - Deferred Taxes - Schedule of Unrecognised Deferred Tax Asset Balance Roll Forward (Detail) Network

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1415 Disclosure of temporary difference, unused tax losses and unused tax credits [table] Table

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*

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1422 34% > 25% [member] Member cyad:ForeignExchangeTaxRateApplicableTwentyFivePercentageToThirtyFourPercentageMember
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1424 Disclosure of temporary difference, unused tax losses and unused tax credits [line items] LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
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1430 1134 - Disclosure - Commitments - Additional Information (Detail) Network

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1431 Disclosure Of Commitments [table] Table

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1450 IND to FDA [member] Member cyad:INDToFDAMember
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1474 1135 - Disclosure - Relationships with Third-Parties - Summary of Remuneration of Key Management Informations (Detail) Network

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1475 Disclosure of key management personnel compensation [table] Table

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1491 Outstanding payables Concept (Monetary) As Of Credit cyad:OutstandingPayablesOfManagementRemuneration
1492 1136 - Disclosure - Relationships with Third-Parties - Summary of Transactions with Non-executive Directors (Detail) Network

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1493 Disclosure of transactions between related parties [table] Table

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1502 Number of warrants lapsed Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExpiredInSharebasedPaymentArrangement
1503 Number of exercised warrants Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
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1506 Shares owned Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
1507 1137 - Disclosure - Relationships with Third-Parties - Summary of Transactions with Shareholders (Detail) Network

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1508 Disclosure of transactions between related parties [table] Table

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1512 Disclosure of transactions between related parties [line items] LineItems ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
1513 Rent Concept (Monetary) For Period ifrs-full:LeasesAsLesseeRelatedPartyTransactions
1514 Other Concept (Monetary) For Period Credit cyad:RelatedPartyTransactionOther
1515 Total Concept (Monetary) For Period Credit cyad:RelatedPartyTransactionNet
1516 Outstanding payables Concept (Monetary) As Of Credit ifrs-full:AmountsPayableRelatedPartyTransactions
1517 1138 - Disclosure - Loss Per Share - Calculation of Earnings (Loss) Per Share (Detail) Network

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1518 Implied Table Table

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1521 Weighted average number of shares outstanding Concept (Shares) For Period ifrs-full:WeightedAverageShares
1522 Earnings per share (non-fully diluted) in € Concept (Share) For Period ifrs-full:BasicEarningsLossPerShare
1523 Outstanding warrants Concept (Shares) For Period cyad:AntidilutiveSecuritiesExcludedFromComputationOfEarningPerShareAmount

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