Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020		Dec. 31, 2019
OPERATING ACTIVITIES
Net income (loss)	$ 1,168	$ 497	[1]	$ 1,202	[1]
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	(384)	537		74
Provision (benefit) for deferred income taxes	79	(82)		14
Depreciation and amortization	99	108		114
Net periodic defined benefit credit	(81)	(55)		(35)
Share-based compensation expense	41	24		39
Net amortization of securities	36	15		2
Net securities losses	0	0		7
Net gains (losses) on sales of foreclosed property	0	(1)		1
Net change in accrued income receivable	13	25		17
Net change in accrued expenses payable	132	(29)		(27)
Other, net	(469)	(111)		(318)
Net cash provided by operating activities	634	928		1,090
INVESTING ACTIVITIES
Maturities and redemptions of investment securities available-for-sale	5,536	3,350		2,262
Sales of investment securities available-for-sale	0	0		987
Purchases of investment securities available-for-sale	(7,936)	(5,804)		(3,346)
Net change in loans	4,067	(2,136)		(324)
Proceeds from sales of foreclosed property	8	5		1
Other, net	(70)	(79)		(86)
Purchases of Federal Home Loan Bank stock	0	(51)		(201)
Redemptions of Federal Home Loan Bank stock	115	92		201
Proceeds from bank-owned life insurance settlements	16	20		10
Other, net	(13)	1		2
Net cash used in investing activities	1,723	(4,602)		(494)
FINANCING ACTIVITIES
Net change in deposits	8,438	15,554		1,711
Net change in short-term borrowings	0	(71)		27
Maturities of medium- and long-term debt	(2,800)	(1,675)		(350)
Issuances and advances of medium- and long-term debt	0	0		1,050
Issuance of preferred stock	0	394		0
Preferred stock cash dividends paid	(23)	(8)		0
Repurchases of common stock	(729)	(199)		(1,394)
Cash dividends paid on common stock	(369)	(375)		(402)
Issuances of common stock under employee stock plans	34	4		18
Other, net	4	(1)		1
Net cash provided by (used in) financing activities	4,555	13,623		661
Net increase (decrease) in cash and cash equivalents	6,912	9,949		1,257
Cash and cash equivalents at beginning of period	15,767	5,818		4,561
Cash and cash equivalents at end of period	22,679	15,767		5,818
Interest paid	57	203		462
Income taxes paid	157	141		266
Noncash investing and financing activities:
Loans transferred to other real estate	$ 1	$ 1		$ 12

[1] See Defined Benefit Pension and Other Postretirement Costs in Note 1.