Stockholders' Equity - Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Before Tax
Net unrealized gains (losses) on securities available for sale	$ (244)	$ (1,171)	$ (1,359)	$ 96
Net unrealized losses on hedging relationships	24	(558)	(518)	(30)
Foreign currency translation adjustments	3	9	6	10
Other	0	0	1	0
Other comprehensive income (loss)	(217)	(1,720)	(1,870)	76
Provision (Benefit)
Net unrealized gains (losses) on securities available for sale	(60)	(283)	(331)	22
Net unrealized losses on hedging relationships	6	(134)	(126)	(7)
Foreign currency translation adjustments	4	(25)	20	(37)
Other	0	0	0	0
Other comprehensive income (loss)	(50)	(442)	(437)	(22)
After Tax
Net unrealized gains (losses) on securities available for sale	(184)	(888)	(1,028)	74
Net unrealized losses on hedging relationships	18	(424)	(392)	(23)
Foreign currency translation adjustments	(1)	34	(14)	47
Other	0	0	1	0
Other comprehensive income (loss), net of tax	$ (167)	$ (1,278)	$ (1,433)	$ 98

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