| Standard label: | Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield |
| Name: | us-gaap:CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield |
| Documentation: | The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYield |
| Label | Role | Language |
| Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield | http://www.xbrl.org/2003/role/label | en-US |
| Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Ending Balance | http://www.xbrl.org/2003/role/periodEndLabel | en-US |
| Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield, Beginning Balance | http://www.xbrl.org/2003/role/periodStartLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 310 30 50 2 (a)(2) | http://fasb.org/us-gaap/role/ref/legacyRef | 310 |
| FASB Accounting Standards Codification 310 30 15 2 | http://fasb.org/us-gaap/role/ref/legacyRef | 310 |