CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Deficit	Accumulated Other Comprehensive Loss	Treasury Stock	Non- controlling Interests
Balance at beginning of period at Dec. 31, 2018	$ 1,535	$ 0	$ 3,802	$ (1,198)	$ (950)	$ (120)	$ 1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(47)			(47)
Purchases of treasury stock	(24)					(24)
Special dividend	0
Stock unit awards vested, net of shares forfeited for employee withholding taxes	0
Other comprehensive income (loss), net of tax	(229)				(229)
Balance at end of period at Dec. 31, 2019	1,235	0	3,802	(1,245)	(1,179)	(144)	1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation, net of withholding taxes	2		2
Net income (loss)	10			10
Purchases of treasury stock	(30)
Special dividend	0
Stock unit awards vested, net of shares forfeited for employee withholding taxes	0
Other comprehensive income (loss), net of tax	(135)				(135)
Balance at end of period at Dec. 31, 2020	1,082	0	3,804	(1,235)	(1,314)	(174)	1
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation, net of withholding taxes	1		1
Net income (loss)	309			307			2
Purchases of treasury stock	(48)
Special dividend	(79)		2	(81)
Stock unit awards vested, net of shares forfeited for employee withholding taxes	0
Other comprehensive income (loss), net of tax	252				252
Balance at end of period at Dec. 31, 2021	$ 1,517	$ 0	$ 3,807	$ (1,009)	$ (1,062)	$ (222)	$ 3