v3.7.0.1

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Income Tax Contingency [Line Items]
Income tax (expense) benefit	$ (63)	$ 14	$ (2)	$ (21)
Effective Income Tax Rate, Continuing Operations	(41.00%)	33.00%	(1.00%)	(10.00%)
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions			$ 17
Unrecognized Tax Benefits	$ 48		48
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	10		10
Unrecognized Tax Benefit Related to Deferred Tax Asset	38		38
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	4		4
Minimum [Member]
Income Tax Contingency [Line Items]
Decrease in Unrecognized Tax Benefits is Reasonably Possible	0		0
Maximum [Member]
Income Tax Contingency [Line Items]
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 7		$ 7

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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

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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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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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