v3.26.1
Derivatives and Hedging Activities - Schedule of Cumulative Basis Adjustments on Fair Value Hedges (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Derivatives, Fair Value [Line Items]    
Fair Value $ 38,459 $ 39,596
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DebtSecuritiesAvailableForSaleExcludingAccruedInterest | Interest rate    
Derivatives, Fair Value [Line Items]    
Carrying amount of hedged item 12,830 12,843
Fair Value 8,100 6,700
Hedged layer amount 5,800 4,900
Hedged asset, fair value hedge, portfolio layer method, hedged layer, fair value, cumulative increase (decrease) 46 (35)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DebtSecuritiesAvailableForSaleExcludingAccruedInterest | Interest rate | Hedge accounting basis adjustment - active hedges    
Derivatives, Fair Value [Line Items]    
Hedge accounting basis adjustment 25 (100)
Hedged asset, fair value hedge, portfolio layer method, hedged layer, fair value, cumulative increase (decrease) 32 (50)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:DebtSecuritiesAvailableForSaleExcludingAccruedInterest | Interest rate | Hedge accounting basis adjustment - discontinued hedges    
Derivatives, Fair Value [Line Items]    
Hedge accounting basis adjustment 14 14
Hedged asset, fair value hedge, portfolio layer method, hedged layer, fair value, cumulative increase (decrease) 14 14
Location, Statement of Financial Position, Balance [Axis]: us-gaap:LongTermDebt | Interest rate    
Derivatives, Fair Value [Line Items]    
Carrying amount of hedged item 8,609 8,504
Location, Statement of Financial Position, Balance [Axis]: us-gaap:LongTermDebt | Interest rate | Hedge accounting basis adjustment - active hedges    
Derivatives, Fair Value [Line Items]    
Hedge accounting basis adjustment (292) (199)
Location, Statement of Financial Position, Balance [Axis]: us-gaap:LongTermDebt | Interest rate | Hedge accounting basis adjustment - discontinued hedges    
Derivatives, Fair Value [Line Items]    
Hedge accounting basis adjustment $ (3) $ (3)