Inventories (Details) - USD ($)	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Inventory valuation adjustment	$ 455,000	$ 0
Components of Inventories
Crude oil	70,526,000		$ 89,683,000
Asphalt and other	9,920,000		9,551,000
Total Inventories	80,446,000		$ 99,234,000
Crude Supply and Logistics [Member]
Inventory valuation adjustment	$ 500,000

No definition available.

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Amount of fossil fuel included in inventory classified as other.

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Carrying amount as of the balance sheet date of petroleum or crude oil.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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