Income Taxes - Components of Income Tax (Benefit) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Current	$ 16	$ 126
Deferred	(100)	(157)
Total Income Tax Benefit	$ (84)	$ (31)
Effective Tax Rate	22.50%	(5.70%)

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Name:	us-gaap_DeferredIncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration