Financial Instruments - Notional amounts (Details) - bbl bbl in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Sales [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	5,890	7,721	16,310	13,452
Purchases [Member]
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume	5,743	7,508	16,253	13,413

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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