Accumulated Other Comprehensive Loss (Schedule of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 12,859	$ 17,050	$ 14,703
Net change	243	(3,901)	(789)
Ending balance	13,766	12,859	17,050
Accumulated other comprehensive income (loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(4,059)	(158)	631
Net change	243	(3,901)	(789)
Ending balance	(3,816)	(4,059)	(158)
Available-for-sale securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	(4,095)	(95)	640
Net change	949	(4,000)	(735)
Ending balance	(3,146)	(4,095)	(95)
Held-to-maturity securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	0	0
Net change	(682)	0	0
Ending balance	(682)	0	0
Translation adjustments and net investment hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	18	19	19
Net change	3	(1)	0
Ending balance	21	18	19
Cash flow hedges
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	18	35	82
Net change	(27)	(17)	(47)
Ending balance	(9)	18	35
Defined benefit pension plans
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	(117)	(110)
Net change	0	117	(7)
Ending balance	$ 0	$ 0	$ (117)