Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 13,851	$ 13,532	$ 13,766	$ 12,859
Net change	616	(902)	423	(706)
Ending balance	14,725	12,825	14,725	12,825
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(4,009)	(3,863)	(3,816)	(4,059)
Net change	616	(902)	423	(706)
Ending balance	(3,393)	(4,765)	(3,393)	(4,765)
Available-for-sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3,353)	(3,881)	(3,146)	(4,095)
Net change	588	(886)	381	(672)
Ending balance	(2,765)	(4,767)	(2,765)	(4,767)
Held-to-maturity securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(650)	0	(682)	0
Net change	18	0	50	0
Ending balance	(632)	0	(632)	0
Translation adjustments and net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	20	21	21	18
Net change	1	(1)	0	2
Ending balance	21	20	21	20
Cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(26)	(3)	(9)	18
Net change	9	(15)	(8)	(36)
Ending balance	$ (17)	$ (18)	$ (17)	$ (18)