Derivative Financial Instruments - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Derivative
Collateral held for derivative assets	$ 947,000,000	$ 1,300,000,000
Variation margin	403,000,000	587,000,000
Valuation adjustments related to the credit risk associated with counterparties of customer accommodation derivative contracts	4,000,000	7,000,000
Amount of variation margin payment applied to derivative liability contracts	1,200,000,000	721,000,000
Gain or losses reclassified from AOCI into earnings associated with the discontinuance of cash flow hedges	0	0
Notional amount of the risk participations agreements	3,247,000,000	3,563,000,000
Total collateral
Derivative
Collateral held for derivative liabilities	$ 1,100,000,000	1,100,000,000
Interest Rate Contract
Derivative
Maximum length of time of hedging exposure	85 months
Deferred loss, net of tax, on cash flow hedges recorded in accumulated other comprehensive income	$ (654,000,000)	(372,000,000)
Net deferred loss, net of tax, recorded in AOCI are expected to be reclassified into earnings	134,000,000
Interest Rate Contract | Credit Risk
Derivative
Fair value of risk participation agreements	$ 5,000,000	$ 6,000,000
Weighted-average remaining life	2 years 1 month 6 days