Lawsuits, Claims, Commitments and Contingencies(Details)	12 Months Ended
Dec. 31, 2017
Arbitration filed by Andes Petroleum Ecuador Ltd
Lawsuits, commitments and contingencies
Percentage of payments claimed (as a percent)	40.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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