Stockholders' Deficit (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2020
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	$ (2,108)	$ (2,463)
Cumulative Effect of New Accounting Principle in Period of Adoption			$ (6)
Net payment in connection with settlement of stock options and RSUs	(1)	2
Stock-based compensation	9	11
Net loss	(155)	(24)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	4	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(97)	51
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	(2,358)	(2,423)
Share-based compensation expense	10	14
Related to SGC stock options
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	1	2
Related to SGC RSUs
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation expense	9	12
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	1	1
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	1	1
Additional Paid in Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	1,208	835
Net payment in connection with settlement of stock options and RSUs	(1)	2
Stock-based compensation	9	11
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	1,216	848
Accumulated Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	(2,954)	(2,824)
Net loss	(159)	(24)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	(3,119)	(2,848)
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	(175)	(175)
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	(175)	(175)
Accumulated Other Comprehensive Loss
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	(292)	(300)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(97)	51
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	(389)	$ (249)
Noncontrolling Interest
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Beginning Balance	104
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Ending Balance	$ 108

Amount of increase to additional paid-in capital (APIC) for recognition of cost for award under share-based payment arrangement.

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