Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Effective Tax Rate
Income from continuing operations before income taxes	$ 188	$ 32	$ 286	$ 276
Income tax (benefit)/expense from continuing operations	$ (1)	$ 5	$ 3	$ 11
Effective income tax rate	(0.50%)	15.60%	1.00%	4.00%
Uncertain Tax Benefits
Non-current tax liability for uncertain tax benefits	$ 28		$ 28
Uncertain tax benefits, penalties and interest accrued	$ 4		$ 4

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount recognized for uncertainty in income taxes classified as noncurrent.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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