Consolidated Statements Of Equity (Deficit) - USD ($) shares in Thousands, $ in Millions	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Common Stock [Member]	Total
Cumulative Effect of New Accounting Principle in Period of Adoption | Accounting Standards Update 2014-09 [Member]			$ 11			$ 11
Cumulative Effect of New Accounting Principle in Period of Adoption | Accounting Standards Update 2018-02 [Member]			79	$ (79)
Balance at Dec. 31, 2018	$ 27	$ 4,802	(2,752)	(463)	$ (14)	1,600
Common Stock Balance (in shares) at Dec. 31, 2018	106,025				(489)
Stock plans		3				3
Stock plans (in shares)					(229)
Net loss			(87)			(87)
Other comprehensive income, net of tax				8		8
Balance at Mar. 31, 2019	$ 27	4,805	(2,749)	(534)	$ (14)	1,535
Common Stock Balance (in shares) at Mar. 31, 2019	106,025				(718)
Balance at Dec. 31, 2019	$ 27	4,815	(8,573)	(650)	$ (13)	$ (4,394)
Common Stock Balance (in shares) at Dec. 31, 2019	106,025				(894)	105,131
Stock plans		1				$ 1
Stock plans (in shares)					(143)
Net loss			(186)			(186)
Other comprehensive income, net of tax				86		86
Balance at Mar. 31, 2020	$ 27	$ 4,816	$ (8,759)	$ (564)	$ (13)	$ (4,493)
Common Stock Balance (in shares) at Mar. 31, 2020	106,025				(1,037)	104,989