Annual report pursuant to Section 13 and 15(d)

Fair Values of Assets and Liabilities (Recurring basis) (Details)

v2.4.1.9
Fair Values of Assets and Liabilities (Recurring basis) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2011
Assets measured at fair value on a recurring basis      
Trading account securities $ 42,191us-gaap_TradingSecurities $ 35,573us-gaap_TradingSecurities  
Available-for-sale and other securities 9,384,670us-gaap_AvailableForSaleSecurities 7,308,753us-gaap_AvailableForSaleSecurities  
MSR's 22,786us-gaap_ServicingAssetAtFairValueAmount 34,236us-gaap_ServicingAssetAtFairValueAmount 35,202us-gaap_ServicingAssetAtFairValueAmount
MortgagesHeldForInvestmentFairValueDisclosure 40,027hban_Mortgagesheldforinvestmentfairvaluedisclosure    
Level 3 [Member] | U.S. Treasury [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities   0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel3Member
 
Recurring Basis [Member]      
Assets measured at fair value on a recurring basis      
Mortgage loans held for sale 354,888us-gaap_MortgagesHeldForSaleFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
278,928us-gaap_MortgagesHeldForSaleFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Trading account securities 42,191us-gaap_TradingSecurities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
35,573us-gaap_TradingSecurities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 9,053,111us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
6,987,762us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Automobile loans 10,590hban_FairValueMeasuredOnRecurringBasisAutomobileLoan
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
52,286hban_FairValueMeasuredOnRecurringBasisAutomobileLoan
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
MSR's 22,786us-gaap_ServicingAssetAtFairValueAmount
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
34,236us-gaap_ServicingAssetAtFairValueAmount
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Derivative assets 352,642us-gaap_DerivativeAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
200,029us-gaap_DerivativeAssets
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Liabilities measured at fair value on a recurring basis      
Derivatives 284,255us-gaap_DerivativeLiabilities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
129,274us-gaap_DerivativeLiabilities
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Short-term borrowings (2,295)us-gaap_SecuritiesBorrowedFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
(1,089)us-gaap_SecuritiesBorrowedFairValueDisclosure
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | U.S. Treasury [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 5,452us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
51,604us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Federal agencies - mortgage backed securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 5,322,701us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
3,566,221us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | TLGP securities [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_TemporaryLiquidityGuaranteeProgramSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Federal agencies: Other agencies [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 2,857us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
834us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 351,543us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
319,888us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Municipal securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 5,098us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
2,180us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 1,868,569us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
1,145,992us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 41,926us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
49,104us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Asset-backed Securities [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 955,998us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
1,091,040us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Covered Bonds [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   285,874us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_BondsMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Corporate debt [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 486,176us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
457,240us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Other securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 34,236us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_OtherDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
32,559us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_OtherDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 20,746us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_OtherDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
20,799us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_OtherDebtSecuritiesMember
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member]      
Assets measured at fair value on a recurring basis      
Mortgage loans held for sale 0us-gaap_MortgagesHeldForSaleFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_MortgagesHeldForSaleFairValueDisclosure
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Trading account securities 33,121us-gaap_TradingSecurities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
32,081us-gaap_TradingSecurities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 22,882us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
68,575us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Automobile loans 0hban_FairValueMeasuredOnRecurringBasisAutomobileLoan
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0hban_FairValueMeasuredOnRecurringBasisAutomobileLoan
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
MSR's 0us-gaap_ServicingAssetAtFairValueAmount
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_ServicingAssetAtFairValueAmount
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Derivative assets 0us-gaap_DerivativeAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
36,774us-gaap_DerivativeAssets
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Liabilities measured at fair value on a recurring basis      
Derivatives 0us-gaap_DerivativeLiabilities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
22,787us-gaap_DerivativeLiabilities
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | U.S. Treasury [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 5,452us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
51,604us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_USTreasurySecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Federal agencies - mortgage backed securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | TLGP securities [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_TemporaryLiquidityGuaranteeProgramSecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Federal agencies: Other agencies [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= hban_OtherFederalAgenciesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Municipal securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_TradingSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MunicipalBondsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_MortgageBackedSecuritiesIssuedByPrivateEnterprisesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Asset-backed Securities [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Covered Bonds [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_BondsMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
Recurring Basis [Member] | Level 1 [Member] | Corporate debt [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities 0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
0us-gaap_AvailableForSaleSecurities
/ us-gaap_FairValueByAssetClassAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_FairValueByFairValueHierarchyLevelAxis
= us-gaap_FairValueInputsLevel1Member
/ us-gaap_FairValueByMeasurementFrequencyAxis
= us-gaap_FairValueMeasurementsRecurringMember
 
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Assets measured at fair value on a recurring basis      
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Assets measured at fair value on a recurring basis      
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Liabilities measured at fair value on a recurring basis      
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Assets measured at fair value on a recurring basis      
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Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 2 [Member] | TLGP securities [Member]      
Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 2 [Member] | Federal agencies: Other agencies [Member]      
Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 2 [Member] | Municipal securities [Member]      
Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 2 [Member] | Mortgage-backed Securities, Issued by Private Enterprises [Member]      
Assets measured at fair value on a recurring basis      
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16,964us-gaap_AvailableForSaleSecurities
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Recurring Basis [Member] | Level 2 [Member] | Asset-backed Securities [Member]      
Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 2 [Member] | Covered Bonds [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   285,874us-gaap_AvailableForSaleSecurities
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Recurring Basis [Member] | Level 2 [Member] | Corporate debt [Member]      
Assets measured at fair value on a recurring basis      
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457,240us-gaap_AvailableForSaleSecurities
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Recurring Basis [Member] | Level 2 [Member] | Other securities [Member]      
Assets measured at fair value on a recurring basis      
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Available-for-sale and other securities 3,316us-gaap_AvailableForSaleSecurities
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3,828us-gaap_AvailableForSaleSecurities
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Recurring Basis [Member] | Level 3 [Member]      
Assets measured at fair value on a recurring basis      
Mortgage loans held for sale 0us-gaap_MortgagesHeldForSaleFairValueDisclosure
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Available-for-sale and other securities 1,530,795us-gaap_AvailableForSaleSecurities
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794,096us-gaap_AvailableForSaleSecurities
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MSR's 22,786us-gaap_ServicingAssetAtFairValueAmount
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Derivative assets 4,064us-gaap_DerivativeAssets
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Liabilities measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 3 [Member] | U.S. Treasury [Member]      
Assets measured at fair value on a recurring basis      
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Recurring Basis [Member] | Level 3 [Member] | Federal agencies - mortgage backed securities [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
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Recurring Basis [Member] | Level 3 [Member] | TLGP securities [Member]      
Assets measured at fair value on a recurring basis      
Available-for-sale and other securities   0us-gaap_AvailableForSaleSecurities
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Recurring Basis [Member] | Level 3 [Member] | Federal agencies: Other agencies [Member]      
Assets measured at fair value on a recurring basis      
Trading account securities 0us-gaap_TradingSecurities
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