Investment Securities - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Gains (losses) from sales of available-for-sale securities, net	$ 79,000,000	$ 294,000,000	$ 2,000,000
Debt securities, AFS, allowance	0	0	2,000,000
Asset Pledged as Collateral
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Pledged securities not separately reported	86,700,000,000	71,300,000,000
ABS and municipal bonds
Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items]
Securities sold	10,970,000,000	4,920,000,000	4,590,000,000
Gains (losses) from sales of available-for-sale securities, net	$ 79,000,000	$ 294,000,000	$ 2,000,000