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Derivatives - Open Commodity Derivative Contracts (Details) gal in Thousands, bbl in Thousands | 9 Months Ended
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Sep. 30, 2019 bbl gal
Exchange Traded | Crude oil |  |
Derivative [Line Items] |  |
Percentage of derivative contracts expiring in the period | 92.10% |
Exchange Traded | Crude oil | Long |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 35,825 | [1]
Exchange Traded | Crude oil | Long | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 6,520 |
Exchange Traded | Crude oil | Short |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | gal | 40,897 | [1]
Exchange Traded | Crude oil | Short | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 1,500 |
Exchange Traded | Refined products |  |
Derivative [Line Items] |  |
Percentage of derivative contracts expiring in the period | 97.10% |
Exchange Traded | Refined products | Long |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 17,014 | [1]
Exchange Traded | Refined products | Long | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 925 |
Exchange Traded | Refined products | Short |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | gal | 11,258 | [1]
Exchange Traded | Refined products | Short | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 225 |
Exchange Traded | Blending products |  |
Derivative [Line Items] |  |
Percentage of derivative contracts expiring in the period | 84.20% |
Exchange Traded | Blending products | Long |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 2,750 | [1]
Exchange Traded | Blending products | Long | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 257 |
Exchange Traded | Blending products | Short |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | gal | 7,708 | [1]
Exchange Traded | Blending products | Short | Spread Contracts |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 182 |
Over the Counter | Crude oil |  |
Derivative [Line Items] |  |
Percentage of derivative contracts expiring in the period | 100.00% |
Over the Counter | Crude oil | Long |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 160 |
Over the Counter | Crude oil | Short |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 0 |
Over the Counter | Blending products |  |
Derivative [Line Items] |  |
Percentage of derivative contracts expiring in the period | 100.00% |
Over the Counter | Blending products | Long |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | 313 |
Over the Counter | Blending products | Short |  |
Derivative [Line Items] |  |
Notional contracts (in thousands of Total Barrels) | gal | 313 |
[1] | Included in exchange-traded are spread contracts in thousands of barrels: Crude oil - 6,520 long and 1,500 short; Refined products - 925 long and 225 short; Blending products - 257 long and 182 short

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