v3.7.0.1

Income Taxes (Income Tax Expense (Benefit)) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Contingency [Line Items]
Income tax (expense) benefit	$ 61	$ (35)
Effective Income Tax Rate, Continuing Operations	52.00%	(21.00%)
Income Tax Uncertainties [Abstract]
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	$ 17
Unrecognized Tax Benefits	48
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	10
Unrecognized Tax Benefit Related to Deferred Tax Asset	38
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	3
Minimum [Member]
Income Tax Contingency [Line Items]
Decrease in Unrecognized Tax Benefits is Reasonably Possible	0
Maximum [Member]
Income Tax Contingency [Line Items]
Decrease in Unrecognized Tax Benefits is Reasonably Possible	$ 7

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

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-Publisher FASB
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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 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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