Stockholders' Equity - Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Before Tax
Net unrealized gains (losses) on securities available for sale	$ 3,033	$ (2,780)	$ 1,674	$ (2,684)
Net unrealized gains (losses) on hedging relationships	1,412	(342)	894	(372)
Foreign currency translation adjustments	2	(2)	8	8
Other			1	0
Other comprehensive income (loss)	4,447	(3,124)	2,577	(3,048)
Provision (Benefit)
Net unrealized gains (losses) on securities available for sale	733	(672)	402	(650)
Net unrealized gains (losses) on hedging relationships	343	(83)	217	(90)
Foreign currency translation adjustments	(43)	37	(23)	0
Other			0	0
Other comprehensive income (loss)	1,033	(718)	596	(740)
After Tax
Net unrealized gains (losses) on securities available for sale	2,300	(2,108)	1,272	(2,034)
Net unrealized gains (losses) on hedging relationships	1,069	(259)	677	(282)
Foreign currency translation adjustments	45	(39)	31	8
Other	0	0	1	0
Other comprehensive income (loss), net of tax	$ 3,414	$ (2,406)	$ 1,981	$ (2,308)

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