Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Accounts receivable, allowance for doubtful accounts	$ 0	$ 24
Property, plant and equipment, accumulated depreciation	104,641	80,768
Intangible assets, accumulated amortization	$ 10,310	$ 9,079
Common Units-Public
Limited partner units issued	13,065,204	12,980,623
Limited partner units outstanding	13,065,204	12,980,623
Common Units-Sponsor
Limited partner units issued	1,347,161	1,347,161
Limited partner units outstanding	1,347,161	1,347,161
Subordinated Units-Sponsor
Limited partner units issued	11,905,138	11,905,138
Limited partner units outstanding	11,905,138	11,905,138
General Partner
General partner units outstanding	0	0

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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