SUPPLEMENTARY OIL AND GAS INFORMATION (UNAUDITED) SUPPLEMENTARY OIL AND GAS INFORMATION (UNAUDITED) (Schedule of Costs Incurred) (Details) $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($)
Property acquisition costs:
Unproved properties	$ 7
Exploration costs	22
Development costs	749
Total	778
Asset Retirement Obligation, Period Increase (Decrease)	37
United States oil and gas operations
Property acquisition costs:
General and Administrative Costs Capitalized	78
Capitalized interest	$ 7

Capitalized general and administrative costs incurred in oil and gas activities.

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Amount of increase (decrease) in asset retirement obligations.

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Costs incurred, including capitalized costs and costs charged to expense, associated with the acquisition of oil and gas properties that have unproved reserves.

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Development costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

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Exploration costs incurred, including capitalized costs and costs charged to expense, in oil and gas activities.

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Amount of costs incurred related to oil and gas property acquisition, exploration and development activities, including capitalized costs and costs charged to expense.

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Amount of interest capitalized during the period.

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