Derivatives - Open Commodity Derivative Contracts - Crude Oil (Details) - Crude Oil - Exchange Traded bbl in Thousands |
3 Months Ended | |||
|---|---|---|---|---|
|
Mar. 31, 2018
bbl
| ||||
| Derivative [Line Items] | ||||
| Percentage of derivative contracts expiring in the period | 94.70% | |||
| Derivative contract expiration date | Jun. 30, 2017 | |||
| Long | ||||
| Derivative [Line Items] | ||||
| Notional contracts (in thousands of Total Barrels) | 16,664 | [1] | ||
| Short | ||||
| Derivative [Line Items] | ||||
| Notional contracts (in thousands of Total Barrels) | 22,145 | [1] | ||
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