Stockholders' Equity - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance			$ 374
Other comprehensive income (loss), net of tax	$ (2,823)	$ 9	(7,290)	$ (1,702)
AOCI ending balance	(6,916)		(6,916)
Securities available for sale | Available-for-sale securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance	(2,956)	1,038	297	2,186
Other comprehensive income (loss) before reclassifications	(2,293)	51	(5,546)	(1,094)
Amounts reclassified from AOCI into earnings	5	0	5	(3)
Other comprehensive income (loss), net of tax	(2,288)	51	(5,541)	(1,097)
AOCI ending balance	(5,244)	1,089	(5,244)	1,089
Hedging Relationships
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance	(1,091)	781	118	1,362
Other comprehensive income (loss) before reclassifications	(412)	193	(1,535)	(145)
Amounts reclassified from AOCI into earnings	(71)	(244)	(157)	(487)
Other comprehensive income (loss), net of tax	(483)	(51)	(1,692)	(632)
AOCI ending balance	(1,574)	730	(1,574)	730
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance	(26)	(12)	(21)	(31)
Other comprehensive income (loss) before reclassifications	(52)	9	(57)	28
Amounts reclassified from AOCI into earnings	0	0	0	0
Other comprehensive income (loss), net of tax	(52)	9	(57)	28
AOCI ending balance	(78)	(3)	(78)	(3)
Other
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance	(20)	(24)	(20)	(23)
Other comprehensive income (loss) before reclassifications	0	0	0	0
Amounts reclassified from AOCI into earnings	0	0	0	(1)
Other comprehensive income (loss), net of tax	0	0	0	(1)
AOCI ending balance	(20)	(24)	(20)	(24)
Total
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI beginning balance	(4,093)	1,783	374	3,494
Other comprehensive income (loss) before reclassifications	(2,757)	253	(7,138)	(1,211)
Amounts reclassified from AOCI into earnings	(66)	(244)	(152)	(491)
Other comprehensive income (loss), net of tax	(2,823)	9	(7,290)	(1,702)
AOCI ending balance	(6,916)	1,792	(6,916)	1,792
Net investment hedges
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Other comprehensive gain (loss)	$ 174	$ (13)	$ 222	$ (34)