Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details)

v3.20.2
DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details)
$ in Millions
 3 Months Ended 9 Months Ended 12 Months Ended
Sep. 30, 2020
USD ($)
Sep. 30, 2019
USD ($)
Sep. 30, 2020
USD ($)
group
Sep. 30, 2019
USD ($)
Dec. 31, 2019
USD ($)
Derivative [Line Items]          
Increase (decrease) to net interest income due to derivative adjustment $ 82 $ (16) $ 151 $ (44)  
Fair value hedging adjustments     (69)   $ (93)
Derivative, Notional Amount 28,671   28,671   25,927
Credit risks from interest rate swaps used for trading purposes 988   988   407
Derivative Liability 110   $ 110   104
Number of primary groups | group     2    
Aggregate credit risk, net of collateral 94   $ 94   22
Investment securities and cash collateral pledged by Huntington 285   285    
Investment securities and cash collateral pledged to Huntington 345   345    
Loans Payable [Member]          
Derivative [Line Items]          
Derivative, Notional Amount 18,375   18,375   18,375
Derivative used in trading activity          
Derivative [Line Items]          
Net derivative asset (liability) 75   75   87
Derivative financial instruments used by Huntington on behalf of customers including offsetting derivatives, notional value 32,000   32,000   30,000
Derivative used in Mortgage Banking Activities          
Derivative [Line Items]          
Derivative, Notional Amount 578   578   778
Derivative, Fair Value, Net 44   44   6
Fair Value Hedging | Designated as Hedging Instrument [Member]          
Derivative [Line Items]          
Derivative, Notional Amount 10,296   10,296   7,540
Fair Value Hedging | Designated as Hedging Instrument [Member] | Loans Payable [Member]          
Derivative [Line Items]          
Derivative, Notional Amount 0   0   0
Cash Flow Hedging | Designated as Hedging Instrument [Member]          
Derivative [Line Items]          
Derivative, Notional Amount 17,375   17,375   18,387
Cash Flow Hedging | Designated as Hedging Instrument [Member] | Loans Payable [Member]          
Derivative [Line Items]          
Derivative, Notional Amount 17,375   17,375   18,375
Commitments to Sell Loans [Member]          
Derivative [Line Items]          
Commitments to sell residential real estate loans $ 2,700   $ 2,700   $ 1,400