Consolidated Statements of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Millions	Total	Cumulative Effect, Period of Adoption, Adjustment	Preferred stock	Common stock	Accumulated paid-in capital	Retained earnings	Retained earnings Cumulative Effect, Period of Adoption, Adjustment	Accumulated other comprehensive income (loss)
Beginning balance at Dec. 31, 2018	$ 7,578	$ (3)	$ 566	$ 0	$ 3,806	$ 3,456	$ (3)	$ (250)
Beginning balance (in shares) at Dec. 31, 2018				187,554
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 816					816
Accounting Standards Update [Extensible List]	Accounting Standards Update 2016-13 [Member]
Other comprehensive loss, net of tax	$ 293							293
Bank common stock repurchased	(1,102)				(1,102)
Bank common stock repurchased (in shares)				(23,531)
Net shares issued from stock warrant exercises (in shares)				8
Net activity under employee plans and related tax benefits (in shares)				1,026
Net activity under employee plans and related tax benefits	31				31
Dividends on preferred stock	(34)					(34)
Dividends on common stock	(226)					(226)
Ending balance at Dec. 31, 2019	7,353	$ 20	566	$ 0	2,735	4,009	$ 20	43
Ending balance (in shares) at Dec. 31, 2019				165,057
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	539					539
Other comprehensive loss, net of tax	282							282
Bank common stock repurchased	$ (76)				(76)
Bank common stock repurchased (in shares)	(1,700)			(1,686)
Net shares issued from stock warrant exercises (in shares)				1
Net activity under employee plans and related tax benefits (in shares)				718
Net activity under employee plans and related tax benefits	$ 27				27
Dividends on preferred stock	(34)					(34)
Dividends on common stock	(225)					(225)
Ending balance at Dec. 31, 2020	$ 7,886		566	$ 0	2,686	4,309		325
Ending balance (in shares) at Dec. 31, 2020	164,090			164,090
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 1,129					1,129
Other comprehensive loss, net of tax	(405)							(405)
Bank common stock repurchased	$ (800)				(800)
Bank common stock repurchased (in shares)	(13,500)			(13,521)
Preferred stock redemption	$ (126)		(126)		3	(3)
Net activity under employee plans and related tax benefits (in shares)				1,056
Net activity under employee plans and related tax benefits	39				39
Dividends on preferred stock	(29)					(29)
Dividends on common stock	(232)					(232)
Change in deferred compensation	1					1
Ending balance at Dec. 31, 2021	$ 7,463		$ 440	$ 0	$ 1,928	$ 5,175		$ (80)
Ending balance (in shares) at Dec. 31, 2021	151,625			151,625