Other Liabilities - Current Table (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Other Liabilities Disclosure [Abstract]
Revenues and royalties due others	$ 488	$ 612
Accrued drilling and production costs	261	216
Joint interest prepayments received	81	74
Accrued compensation and benefits	156	214
Other accrued taxes	104	43
Other	187	296
Current liabilities	$ 1,277	$ 1,455

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for royalties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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