Unaudited Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Income Statement [Abstract]
Revenue	$ 68,483	$ 90,376
Costs of services	60,528	80,353
Gross margin	7,955	10,023
Operating costs and expense:
General and administrative	5,940	6,231
Depreciation, amortization and accretion	1,208	1,104
Gain on asset disposals, net	(12)	(21)
Operating income	819	2,709
Other (expense) income:
Interest expense, net	(1,124)	(1,311)
Foreign currency (losses) gains	(457)	101
Other, net	105	88
Net (loss) income before income tax expense	(657)	1,587
Income tax expense	220	206
Net (loss) income	(877)	1,381
Net loss attributable to noncontrolling interests	(88)	(219)
Net (loss) income attributable to limited partners	(789)	1,600
Net income attributable to preferred unitholder	1,033	1,033
Net (loss) income attributable to common unitholders	$ (1,822)	$ 567
Net (loss) income per common limited partner unit:
Basic and diluted (in dollars per share)	$ (0.15)	$ 0.05
Weighted average common units outstanding:
Basic (in units)	12,096	11,971
Diluted (in units)	12,096	12,355