Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 13,657	$ 13,378	$ 13,766	$ 12,859
Net change	(20)	(87)	(193)	196
Ending balance	13,851	13,532	13,851	13,532
Accumulated other comprehensive loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3,989)	(3,776)	(3,816)	(4,059)
Net change	(20)	(87)	(193)	196
Ending balance	(4,009)	(3,863)	(4,009)	(3,863)
Available-for-sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(3,317)	(3,811)	(3,146)	(4,095)
Net change	(36)	(70)	(207)	214
Ending balance	(3,353)	(3,881)	(3,353)	(3,881)
Held-to-maturity securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(667)	0	(682)	0
Net change	17	0	32	0
Ending balance	(650)	0	(650)	0
Translation adjustments and net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	20	18	21	18
Net change	0	3	(1)	3
Ending balance	20	21	20	21
Cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(25)	17	(9)	18
Net change	(1)	(20)	(17)	(21)
Ending balance	$ (26)	$ (3)	$ (26)	$ (3)