Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 15,413	$ 14,625	$ 17,050	$ 14,703
Net change	(1,218)	189	(2,851)	(415)
Ending balance	13,984	17,530	13,984	17,530
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,791)	27	(158)	631
Ending balance	(3,009)	216	(3,009)	216
Unrealized gains on investment securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(1,726)	53	(95)	640
Net change	(1,214)	206	(2,845)	(381)
Ending balance	(2,940)	259	(2,940)	259
Translation adjustments and net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	20	20	19	19
Net change	(1)	0	0	1
Ending balance	19	20	19	20
Cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	30	65	35	82
Net change	(3)	(17)	(8)	(34)
Ending balance	27	48	27	48
Defined benefit pension plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(115)	(111)	(117)	(110)
Net change	0	0	2	(1)
Ending balance	$ (115)	$ (111)	$ (115)	$ (111)