v3.26.1
Derivatives and Hedging Activities - Schedule of Effect of Fair Value and Cash Flow Hedges on Income (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Derivative Instruments, Gain (Loss) [Line Items]        
Interest expense — Long-term debt $ (155) $ (198) $ (306) $ (391)
Interest income – loans 1,463 1,443 2,879 2,844
Interest Income - securities 367 411 737 803
Investment banking and debt placement fees 169 178 366 353
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeSecuritiesHeldToMaturity | Fair Value Hedging        
Net gains (losses) on fair value hedging relationships        
Recognized on hedged items     (125)  
Recognized on derivatives designated as hedging instruments     105  
Net income (expense) recognized on fair value hedges     (20)  
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndDividendIncomeSecuritiesHeldToMaturity | Cash Flow Hedging        
Net gain (loss) on cash flow hedging relationships        
Realized gains (losses) (pre-tax) reclassified from AOCI into net income     0  
Net income (expense) recognized on cash flow hedges     0  
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio | Fair Value Hedging        
Net gains (losses) on fair value hedging relationships        
Recognized on hedged items 0 0 0 0
Recognized on derivatives designated as hedging instruments 0 0 0 0
Net income (expense) recognized on fair value hedges 0 0 0 0
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestAndFeeIncomeLoansAndLeasesHeldInPortfolio | Cash Flow Hedging        
Net gain (loss) on cash flow hedging relationships        
Realized gains (losses) (pre-tax) reclassified from AOCI into net income (28) (90) (64) (183)
Net income (expense) recognized on cash flow hedges (28) (90) (64) (183)
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestExpenseLongTermDebt | Fair Value Hedging        
Net gains (losses) on fair value hedging relationships        
Recognized on hedged items 64 (99) 93 (252)
Recognized on derivatives designated as hedging instruments (84) 51 (135) 159
Net income (expense) recognized on fair value hedges (20) (48) (42) (93)
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestExpenseLongTermDebt | Cash Flow Hedging        
Net gain (loss) on cash flow hedging relationships        
Realized gains (losses) (pre-tax) reclassified from AOCI into net income 0 (1) (1) (2)
Net income (expense) recognized on cash flow hedges 0 (1) (1) (2)
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestIncomeDebtSecuritiesAvailableForSaleOperating | Fair Value Hedging        
Net gains (losses) on fair value hedging relationships        
Recognized on hedged items (64) 37   115
Recognized on derivatives designated as hedging instruments 54 (31)   (102)
Net income (expense) recognized on fair value hedges (10) 6   13
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InterestIncomeDebtSecuritiesAvailableForSaleOperating | Cash Flow Hedging        
Net gain (loss) on cash flow hedging relationships        
Realized gains (losses) (pre-tax) reclassified from AOCI into net income 0 0   0
Net income (expense) recognized on cash flow hedges 0 0   0
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions | Fair Value Hedging        
Net gains (losses) on fair value hedging relationships        
Recognized on hedged items 0 0 0 0
Recognized on derivatives designated as hedging instruments 0 0 0 0
Net income (expense) recognized on fair value hedges 0 0 0 0
Interest rate | Location, Statement of Income, Balance [Axis]: us-gaap:InvestmentBankingAdvisoryBrokerageAndUnderwritingFeesAndCommissions | Cash Flow Hedging        
Net gain (loss) on cash flow hedging relationships        
Realized gains (losses) (pre-tax) reclassified from AOCI into net income 1 0 1 0
Net income (expense) recognized on cash flow hedges $ 1 $ 0 $ 1 $ 0