| Line | Label | Object Class (Data type) | Period Type | Balance | Report Element Name | 
        
           | 1 | Long-term Debt Instruments, by Instrument [Table] | Table |  |  | us-gaap:DebtInstrumentTable | 
        
           | 2 | Legal Entity [Axis] | Axis |  |  | dei:LegalEntityAxis | 
        
           | 3 | Consolidated Entity [Domain] | Member |  |  | dei:EntityDomain | 
        
           | 4 | Long-term Debt, Type [Axis] | Axis |  |  | us-gaap:LongtermDebtTypeAxis | 
        
           | 5 | Long-term Debt, Type [Domain] | Member |  |  | us-gaap:LongtermDebtTypeDomain | 
        
           | 6 | Notes Payable to Banks [Member] | Member |  |  | us-gaap:NotesPayableToBanksMember | 
        
           | 7 | Notes Payable, Other Payables [Member] | Member |  |  | us-gaap:NotesPayableOtherPayablesMember | 
        
           | 8 | Loans Payable [Member] | Member |  |  | us-gaap:LoansPayableMember | 
        
           | 9 | Medium-term Notes [Member] | Member |  |  | us-gaap:MediumTermNotesMember | 
        
           | 10 | Line of Credit [Member] | Member |  |  | us-gaap:LineOfCreditMember | 
        
           | 11 | Secured Debt [Member] | Member |  |  | us-gaap:SecuredDebtMember | 
        
           | 12 | Equipment Trust Certificate [Member] | Member |  |  | us-gaap:EquipmentTrustCertificateMember | 
        
           | 13 | Enhanced Equipment Trust Certificate [Member] | Member |  |  | us-gaap:EnhancedEquipmentTrustCertificateMember | 
        
           | 14 | Convertible Debt [Member] | Member |  |  | us-gaap:ConvertibleDebtMember | 
        
           | 15 | Unsecured Debt [Member] | Member |  |  | us-gaap:UnsecuredDebtMember | 
        
           | 16 | Capital Lease Obligations [Member] | Member |  |  | us-gaap:CapitalLeaseObligationsMember | 
        
           | 17 | Commercial Paper [Member] | Member |  |  | us-gaap:CommercialPaperMember | 
        
           | 18 | Construction Loans [Member] | Member |  |  | us-gaap:ConstructionLoansMember | 
        
           | 19 | Subordinated Debt [Member] | Member |  |  | us-gaap:SubordinatedDebtMember | 
        
           | 20 | Convertible Subordinated Debt [Member] | Member |  |  | us-gaap:ConvertibleSubordinatedDebtMember | 
        
           | 21 | Junior Subordinated Debt [Member] | Member |  |  | us-gaap:JuniorSubordinatedDebtMember | 
        
           | 22 | Mortgages [Member] | Member |  |  | us-gaap:MortgagesMember | 
        
           | 23 | Participating Mortgages [Member] | Member |  |  | us-gaap:ParticipatingMortgagesMember | 
        
           | 24 | Bridge Loan [Member] | Member |  |  | us-gaap:BridgeLoanMember | 
        
           | 25 | Federal Home Loan Bank Advances [Member] | Member |  |  | us-gaap:FederalHomeLoanBankAdvancesMember | 
        
           | 26 | Corporate Debt Securities [Member] | Member |  |  | us-gaap:CorporateDebtSecuritiesMember | 
        
           | 27 | Debt Instrument [Axis] | Axis |  |  | us-gaap:DebtInstrumentAxis | 
        
           | 28 | Debt Instrument, Name [Domain] | Member |  |  | us-gaap:DebtInstrumentNameDomain | 
        
           | 29 | Debt Instrument [Line Items] | LineItems |  |  | us-gaap:DebtInstrumentLineItems | 
        
           | 30 | Debt Instrument [Hierarchy] | Abstract |  |  | added:DebtInstrumentHierarchy | 
        
           | 31 | Debt Instrument, Issuer | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentIssuer | 
        
           | 32 | Debt Instrument, Committee for Uniform Securities Identification Procedures (CUSIP) | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentCommitteeForUniformSecuritiesIdentificationProceduresCUSIP | 
        
           | 33 | Debt Instrument, Currency | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentCurrency | 
        
           | 34 | Debt Instrument, Priority | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentPriority | 
        
           | 35 | Debt Instrument, Collateral | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentCollateral | 
        
           | 36 | Long-term Debt, Gross | Concept  (Monetary) | As Of | Credit | us-gaap:DebtInstrumentCarryingAmount | 
        
           | 37 | Debt Instrument, Face Amount | Concept  (Monetary) | As Of | Credit | us-gaap:DebtInstrumentFaceAmount | 
        
           | 38 | Long-term Debt, Fair Value | Concept  (Monetary) | As Of | Credit | us-gaap:LongTermDebtFairValue | 
        
           | 39 | Long-term Debt, Weighted Average Interest Rate | Concept  (Percent) | As Of |  | us-gaap:LongtermDebtWeightedAverageInterestRate | 
        
           | 40 | Debt, Weighted Average Interest Rate | Concept  (Percent) | As Of |  | us-gaap:DebtWeightedAverageInterestRate | 
        
           | 41 | Debt Instrument, Payment Terms | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentPaymentTerms | 
        
           | 42 | Debt Instrument, Issuance Date | Concept  (Date String) | For Period |  | us-gaap:DebtInstrumentIssuanceDate | 
        
           | 43 | Debt Instrument, Maturity Date, Description | Concept  (Text/String) | For Period |  | us-gaap:DebtInstrumentMaturityDateDescription |