CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Accounts receivable, allowance for doubtful accounts	$ 17	$ 38
Receivables from related parties, allowance for doubtful accounts	0	225
Accumulated Depreciation, Assets held for sale	(1,442)	0
Accumulated depreciation	$ 216,792	$ 205,967
Partners’ capital:
Common unitholders, units issued	33,213,513	33,039,818
Common unitholders, units outstanding	33,213,513	33,039,818
Series A Preferred unitholders, units issued	30,147,624	30,158,619
Series A Preferred unitholders, units outstandingutstanding	30,147,624	30,158,619
General partner interest, units outstanding	1,127,755	1,127,755
General partner percentage interest	1.80%	1.80%