Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Adoption of New Accounting Standard	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Retained Earnings Adoption of New Accounting Standard	Accumulated Other Comprehensive Income (Loss)	Treasury Stock
Balance at beginning of period at Dec. 31, 2018	$ 4,608		$ 107	$ 3	$ 4,049	$ 576		$ (106)	$ (21)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	428					387		41
Dividends declared:
Preferred stock	(8)					(8)
Common stock	(157)					(157)
Issuance of common stock	0				6				(6)
Restricted stock compensation	12				12
Balance at end of period at Dec. 31, 2019	4,883	$ (50)	107	3	4,067	798	$ (50)	(65)	(27)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	312					286		26
Dividends declared:
Preferred stock	(8)					(8)
Common stock	(157)					(157)
Issuance of common stock	1				4				(3)
Repurchase of common stock	(38)								(38)
Restricted stock compensation	16				16
Balance at end of period at Dec. 31, 2020	4,959		107	3	4,087	869		(39)	(68)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Comprehensive income (loss)	382					405		(23)
Dividends declared:
Preferred stock	(8)					(8)
Common stock	(156)					(156)
Issuance of common stock	(3)				3				(6)
Repurchase of common stock	(43)								(43)
Restricted stock compensation	19				19
Balance at end of period at Dec. 31, 2021	$ 5,150		$ 107	$ 3	$ 4,109	$ 1,110		$ (62)	$ (117)