Income Taxes - Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
U.K.	$ (1)	$ 80	$ 76
Non-U.K.	(19)	(245)	110
(Loss) income from continuing operations before income taxes	$ (20)	$ (165)	$ 186

The portion of earnings or loss from continuing operations before income taxes that is attributable to domestic operations.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
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- Definition

The portion of earnings or loss from continuing operations before income taxes that is attributable to foreign operations, which is defined as Income or Loss generated from operations located outside the entity's country of domicile.

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