Investment Securities (Investment Portfolio) (Details) - USD ($) $ in Millions		Dec. 31, 2022	Dec. 31, 2021
Available-for-sale securities
Total		$ 34,863	$ 33,650
Gross unrealized gains		5	358
Gross unrealized losses		(5,327)	(421)
Fair value	[1]	29,541	33,587
Held-to-maturity securities
Amortized cost		1,062	1,170
Gross unrealized gains		0	48
Gross unrealized losses		(178)	(14)
Fair value		884	1,204
Hedged liability, fair value hedge, cumulative increase (decrease)		(12)
Hedged asset, fair value hedge, cumulative increase (decrease)		15
Debt securities, available-for-sale, accrued interest receivable		$ 91	$ 84
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]		Other assets	Other assets
Debt securities, held-to-maturity, accrued interest receivable		$ 2	$ 3
Operating Segments | Insurance operations
Held-to-maturity securities
Deposit securities		12	13
Asset Pledged as Collateral with Right
Available-for-sale securities
Fair value		3,900	203
Held-to-maturity securities
Securities with the right to sell or pledge		899	203
Asset Pledged as Collateral with Right | Federal Home Loan Bank advances
Held-to-maturity securities
Securities with the right to sell or pledge		3,000
U.S. Treasury and federal agencies
Available-for-sale securities
Total		2,272	2,173
Gross unrealized gains		0	2
Gross unrealized losses		(256)	(20)
Fair value		2,016	2,155
U.S. States and political subdivisions
Available-for-sale securities
Total		841	841
Gross unrealized gains		1	27
Gross unrealized losses		(82)	(4)
Fair value		760	864
Foreign government
Available-for-sale securities
Total		158	157
Gross unrealized gains		0	2
Gross unrealized losses		(12)	(2)
Fair value		146	157
Agency mortgage-backed security
Available-for-sale securities
Total		19,668	19,044
Gross unrealized gains		3	219
Gross unrealized losses		(3,038)	(224)
Fair value		16,633	19,039
Held-to-maturity securities
Amortized cost		1,062	1,170
Gross unrealized gains		0	48
Gross unrealized losses		(178)	(14)
Fair value		884	1,204
Mortgage-backed residential
Available-for-sale securities
Total		5,154	4,448
Gross unrealized gains		0	11
Gross unrealized losses		(855)	(34)
Fair value		4,299	4,425
Agency mortgage-backed commercial
Available-for-sale securities
Total		4,380	4,573
Gross unrealized gains		0	66
Gross unrealized losses		(845)	(113)
Fair value		3,535	4,526
Asset-backed
Available-for-sale securities
Total		459	536
Gross unrealized gains		0	1
Gross unrealized losses		(26)	(3)
Fair value		433	534
Corporate debt
Available-for-sale securities
Total		1,931	1,878
Gross unrealized gains		1	30
Gross unrealized losses		(213)	(21)
Fair value		$ 1,719	$ 1,887

[1] Refer to Note 8 for discussion of investment securities pledged as collateral.