Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details)

v3.21.1
DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details)
$ in Millions
 3 Months Ended 6 Months Ended
Mar. 31, 2021
USD ($)
group
Mar. 31, 2020
USD ($)
Jun. 30, 2020
USD ($)
Dec. 31, 2020
USD ($)
Derivative [Line Items]        
Increase (decrease) to net interest income due to derivative adjustment $ 225 $ 16    
Fair value hedging adjustments (50)   $ (62)  
Derivative, Notional Amount 34,208     $ 33,327
Credit risks from interest rate swaps used for trading purposes 593     882
Derivative Liability $ 171     116
Number of primary groups | group 2      
Aggregate credit risk, net of collateral $ 420     175
Investment securities and cash collateral pledged by Huntington 69      
Investment securities and cash collateral pledged to Huntington 434      
Loans Payable [Member]        
Derivative [Line Items]        
Derivative, Notional Amount 17,621     18,646
Derivative used in trading activity        
Derivative [Line Items]        
Net derivative asset (liability) 73     70
Derivative financial instruments used by Huntington on behalf of customers including offsetting derivatives, notional value 46,000     37,000
Derivative used in Mortgage Banking Activities        
Derivative [Line Items]        
Derivative, Notional Amount 875     1,170
Derivative, Fair Value, Net 65     26
Fair Value Hedging | Designated as Hedging Instrument [Member]        
Derivative [Line Items]        
Derivative, Notional Amount 8,587     9,681
Fair Value Hedging | Designated as Hedging Instrument [Member] | Loans Payable [Member]        
Derivative [Line Items]        
Derivative, Notional Amount 0     0
Cash Flow Hedging | Designated as Hedging Instrument [Member]        
Derivative [Line Items]        
Derivative, Notional Amount 16,350     17,375
Cash Flow Hedging | Designated as Hedging Instrument [Member] | Loans Payable [Member]        
Derivative [Line Items]        
Derivative, Notional Amount 16,350     17,375
Commitments to Sell Loans [Member]        
Derivative [Line Items]        
Commitments to sell residential real estate loans $ 2,900     $ 2,900