This item represents disclosure of the amount of dividends or other distributions received from unconsolidated subsidiaries, certain corporate joint ventures, and certain noncontrolled corporation; these investments are accounted for under the equity method of accounting. This element excludes distributions that constitute a return of investment, which are classified as investing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Equity Method Investments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Dec. 31, 2015	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Schedule Of Equity Method Investments [Line Items]
GPT Impairment	$ 6,000
Equity Method Investments		$ 5,712		$ 8,581
Distributions of income from unconsolidated affiliates		$ 3,500	$ 1,500
Venture Fuels Partnership
Schedule Of Equity Method Investments [Line Items]
Equity investment in Venture Fuels Partnership (as a percent)		50.00%
Equity Method Investments		$ 4,698		7,575
Distributions of income from unconsolidated affiliates		3,500	$ 1,500
Other Investment [Member]
Schedule Of Equity Method Investments [Line Items]
Equity Method Investments		$ 1,014		$ 1,006