Stockholders' Equity - Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Before Tax
Net unrealized gains (losses) on securities available for sale	$ (1,115)	$ 1,267
Net unrealized gains (losses) on hedging relationships	(542)	528
Foreign currency translation adjustments	3	1
Other	1	0
Other comprehensive income (loss)	(1,653)	1,796
Provision (Benefit)
Net unrealized gains (losses) on securities available for sale	(271)	305
Net unrealized gains (losses) on hedging relationships	(132)	127
Foreign currency translation adjustments	16	(12)
Other	0	0
Other comprehensive income (loss)	(387)	420
After Tax
Net unrealized gains (losses) on securities available for sale	(844)	962
Net unrealized gains (losses) on hedging relationships	(410)	401
Foreign currency translation adjustments	(13)	13
Other	1	0
Other comprehensive income (loss), net of tax	$ (1,266)	$ 1,376

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