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

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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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Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended
Income Taxes (Details) - USD ($) $ in Millions	Mar. 31, 2017	Mar. 31, 2016	Mar. 29, 2017
Income Taxes (Textual) [Abstract]
Effective tax rate	358.00%	35.00%
Current Income Tax Expense Benefit [Line Items]
Income Tax Expense (Benefit)	$ (831)	$ (768)
Foster Creek Christina Lake (FCCL) and western Canada gas properties [Member] \| Oil and Gas Properties [Member] \| Scenario, Plan [Member] \| Disposal Group Held for sale Not Discontinued Operations [Member]
Current Income Tax Expense Benefit [Line Items]
Income Tax Expense (Benefit)	(800)
Deferred Tax Assets, Valuation Allowance	800
Foster Creek Christina Lake (FCCL) [Member]
Current Income Tax Expense Benefit [Line Items]
Percent interest			50.00%
CANADA \| Foster Creek Christina Lake (FCCL) and western Canada gas properties [Member]
Current Income Tax Expense Benefit [Line Items]
Foreign Tax Benefit/Expense	$ 996