Shareholders' Equity - Accumulated Other Comprehensive Income by Component (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 26,200	$ 24,431	$ 24,737
Other comprehensive income (loss) before reclassifications	(1,255)	1,106
Amounts reclassified into (out of) accumulated other comprehensive loss	(65)	(43)
Other comprehensive income (loss)		1,063
Other comprehensive income (loss)	(1,320)	1,063	564
Ending balance	27,363	26,200	24,431
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	187	(876)	(1,356)
Other comprehensive income (loss)	(1,320)	1,063	564
Ending balance	(1,133)	187	(876)
Net Unrealized Gains (Losses) on Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	57	(70)
Other comprehensive income (loss) before reclassifications	11	179
Amounts reclassified into (out of) accumulated other comprehensive loss	(70)	(52)
Other comprehensive income (loss)		127
Other comprehensive income (loss)	(59)
Ending balance	(2)	57	(70)
Net Unrealized Gains (Losses) on Available-for-Sale Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	848	409
Other comprehensive income (loss) before reclassifications	(854)	439
Amounts reclassified into (out of) accumulated other comprehensive loss	(42)	0
Other comprehensive income (loss)		439
Other comprehensive income (loss)	(896)
Ending balance	(48)	848	409
Net Unrealized Gains (Losses) on Hedges of Net Investments in Non-U.S. Subsidiaries
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(204)	46
Other comprehensive income (loss) before reclassifications	272	(250)
Amounts reclassified into (out of) accumulated other comprehensive loss	0	0
Other comprehensive income (loss)		(250)
Other comprehensive income (loss)	272
Ending balance	68	(204)	46
Other-Than-Temporary Impairment on Held-to-Maturity Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(2)	(2)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified into (out of) accumulated other comprehensive loss	0	0
Other comprehensive income (loss)		0
Other comprehensive income (loss)	0
Ending balance	(2)	(2)	(2)
Net Unrealized Losses on Retirement Plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(178)	(187)
Other comprehensive income (loss) before reclassifications	1	0
Amounts reclassified into (out of) accumulated other comprehensive loss	47	9
Other comprehensive income (loss)		9
Other comprehensive income (loss)	48
Ending balance	(130)	(178)	(187)
Foreign Currency Translation
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(334)	(1,072)
Other comprehensive income (loss) before reclassifications	(685)	738
Amounts reclassified into (out of) accumulated other comprehensive loss	0	0
Other comprehensive income (loss)		738
Other comprehensive income (loss)	(685)
Ending balance	$ (1,019)	$ (334)	$ (1,072)