Condensed Consolidated Statements Of Changes In Equity (Unaudited) - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Retained Earnings (Deficit)	Treasury Stock	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2018	$ 1,516	$ 1	$ 1,954	$ 2,609	$ (1,760)	$ (1,288)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	246			246
Dividends declared	(72)			(72)
Stock compensation	(11)		(11)
Other comprehensive income (loss), net of tax	37					37
Treasury stock activity	(88)				(88)
Balance at Jun. 30, 2019	1,628	1	1,943	2,783	(1,848)	(1,251)
Balance at Mar. 31, 2019	1,563	1	1,936	2,691	(1,796)	(1,269)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	128			128
Dividends declared	(36)			(36)
Stock compensation	7		7
Other comprehensive income (loss), net of tax	18					18
Treasury stock activity	(52)				(52)
Balance at Jun. 30, 2019	1,628	1	1,943	2,783	(1,848)	(1,251)
Balance at Dec. 31, 2019	1,588	1	1,961	3,009	(1,974)	(1,409)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	225			225
Dividends declared	(84)			(84)
Other comprehensive income (loss), net of tax	33					33
Treasury stock activity	(84)				(84)
Balance at Jun. 30, 2020	1,678	1	1,961	3,150	(2,058)	(1,376)
Balance at Mar. 31, 2020	1,643	1	1,955	3,139	(2,058)	(1,394)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings (loss)	53			53
Dividends declared	(42)			(42)
Stock compensation	6		6
Other comprehensive income (loss), net of tax	18					18
Balance at Jun. 30, 2020	$ 1,678	$ 1	$ 1,961	$ 3,150	$ (2,058)	$ (1,376)