Quarterly report pursuant to Section 13 or 15(d)

Derivative Financial Instruments (Details Textuals)

v2.4.1.9
Derivative Financial Instruments (Details Textuals) (USD $)
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Dec. 31, 2014
Derivative Financial Instruments (Textuals) [Abstract]      
Credit risks from interest rate swaps used for trading purposes $ 267,500,000hban_CreditRisksFromInterestRateSwapsUsedForTradingPurposes   $ 219,300,000hban_CreditRisksFromInterestRateSwapsUsedForTradingPurposes
Purchase of interest rate caps and derivative financial instruments, notional value     600,000,000invest_DerivativeNotionalAmount
Total notional amount corresponds to trading assets, fair value 3,500,000hban_NotionalAmountCorrespondsToTradingAssetsFairValue    
Additional Derivative Financial Instruments (Textuals) [Abstract]      
Aggregate credit risk, net of collateral 16,000,000hban_AggregateCreditRiskNetOfCollateral   19,500,000hban_AggregateCreditRiskNetOfCollateral
Investment securities and cash collateral pledged by Huntington 120,600,000us-gaap_CollateralAlreadyPostedAggregateFairValue    
Investment securities and cash collateral pledged to Huntington 176,600,000hban_InvestmentSecuritiesAndCashCollateralPledgedToCompany    
Increase (decrease) to net interest income due to derivative adjustment 24,700,000hban_IncreaseDecreaseToNetInterestIncomeDueToDerivativeAdjustment 24,600,000hban_IncreaseDecreaseToNetInterestIncomeDueToDerivativeAdjustment  
Expected after-tax unrealized gains on cash flow hedging derivatives reclassified to earnings 22,200,000us-gaap_InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet    
Swap [Member]      
Derivative Financial Instruments (Textuals) [Abstract]      
Total derivative liabilities 400,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeByNatureAxis
= us-gaap_SwapMember 		   
Derivative used in trading activity [Member]      
Derivative Financial Instruments (Textuals) [Abstract]      
Net derivative asset (liability) 82,700,000us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInTradingActivityMember 		  74,400,000us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInTradingActivityMember
Derivative financial instruments used by Huntington on behalf of customers including offsetting derivatives, notional value 15,200,000,000hban_DerivativeFinancialInstrumentsUsedByCompanyOnBehalfOfCustomersIncludingOffsettingDerivativesNotionalValue
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInTradingActivityMember 		  14,400,000,000hban_DerivativeFinancialInstrumentsUsedByCompanyOnBehalfOfCustomersIncludingOffsettingDerivativesNotionalValue
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInTradingActivityMember
Derivative used in Mortgage Banking Activities [Member]      
Derivative Financial Instruments (Textuals) [Abstract]      
Net derivative asset (liability) 4,682,000us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember 		  80,000us-gaap_DerivativeAssetsLiabilitiesAtFairValueNet
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember
Purchase of interest rate caps and derivative financial instruments, notional value 700,000,000invest_DerivativeNotionalAmount
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember 		   
Gains (losses) related to derivative instruments Included in total MSR 4,700,000hban_GainsLossesRelatedToDerivativeInstrumentsIncludedInMortgageSecurities
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember 		   
Total derivative liabilities $ 4,156,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember 		  $ 4,019,000us-gaap_DerivativeFairValueOfDerivativeLiability
/ us-gaap_DerivativeByNatureAxis
= hban_DerivativeUsedInMortgageBankingActivitiesMember