Goodwill and Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2016
Roll forward of the Partnership's goodwill
Goodwill, Beginning Balance	$ 312,401
Impairment		$ (121,752)
Disposals	(3,861)
Goodwill, Ending Balance	327,406
Cheshire Oil Company [Member]
Roll forward of the Partnership's goodwill
Acquisition	527
Champlain Oil Company [Member]
Roll forward of the Partnership's goodwill
Acquisition	18,478
Honey Farms Acquisition [Member]
Roll forward of the Partnership's goodwill
Goodwill, Beginning Balance	21,630
Acquisition of Honey Farms - change in goodwill	(139)
Goodwill, Ending Balance	$ 21,491

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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