Accumulated Other Comprehensive Income - Activity in AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), pre-tax activity	$ (8,284)	$ (1,826)	$ 1,836
Other comprehensive income (loss), tax effect	1,967	432	(427)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	22,210	23,111	21,203
Other comprehensive (loss) income, net of tax	(6,317)	(1,394)	1,409
Ending balance	17,327	22,210	23,111
Net unrealized gains on available-for-sale debt securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, pre-tax activity	(7,194)	(1,366)	1,514
Other comprehensive income (loss), before reclassifications, tax effect	1,716	323	(361)
Other comprehensive income (loss), before reclassifications, net activity	(5,478)	(1,043)	1,153
Reclassification adjustment, pre-tax activity	(2)	4	(45)
Reclassification adjustment, tax effect	0	(1)	11
Reclassification adjustment, net activity	(2)	3	(34)
Other comprehensive income (loss), pre-tax activity	(7,196)	(1,362)	1,469
Other comprehensive income (loss), tax effect	1,716	322	(350)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	891	1,931	812
Other comprehensive (loss) income, net of tax	(5,480)	(1,040)	1,119
Ending balance	(4,589)	891	1,931
Net unrealized gains on cash flow hedge derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, pre-tax activity	(1,006)	(185)	611
Other comprehensive income (loss), before reclassifications, tax effect	232	43	(128)
Other comprehensive income (loss), before reclassifications, net activity	(774)	(142)	483
Reclassification adjustment, pre-tax activity	(99)	(293)	(237)
Reclassification adjustment, tax effect	22	70	50
Reclassification adjustment, net activity	(77)	(223)	(187)
Other comprehensive income (loss), pre-tax activity	(1,105)	(478)	374
Other comprehensive income (loss), tax effect	254	113	(78)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	353	718	422
Other comprehensive (loss) income, net of tax	(851)	(365)	296
Ending balance	(498)	353	718
Defined benefit pension plans, net
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss) before reclassifications, pre-tax activity	11	5	(12)
Other comprehensive income (loss), before reclassifications, tax effect	(2)	(1)	3
Other comprehensive income (loss), before reclassifications, net activity	9	4	(9)
Reclassification adjustment, pre-tax activity	6	9	9
Reclassification adjustment, tax effect	(1)	(2)	(2)
Reclassification adjustment, net activity	5	7	7
Other comprehensive income (loss), pre-tax activity	17	14	(3)
Other comprehensive income (loss), tax effect	(3)	(3)	1
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(33)	(44)	(42)
Other comprehensive (loss) income, net of tax	14	11	(2)
Ending balance	(19)	(33)	(44)
Other
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income (loss), pre-tax activity	0	0	(4)
Other comprehensive income (loss), tax effect	0	0	0
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	(4)	(4)	0
Other comprehensive (loss) income, net of tax	0	0	(4)
Ending balance	(4)	(4)	(4)
AOCI
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Beginning balance	1,207	2,601	1,192
Ending balance	$ (5,110)	$ 1,207	$ 2,601