Business Segments (Details) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($) segment	Dec. 31, 2019 USD ($)
Business segments
Number of reportable segments | segment	3
Number of operating segments | segment	3	3
Revenue	$ 71,655		$ 81,982
Adjusted gross profit	39,768	$ 46,080
Total assets	593,188		600,792
Operating Segments
Business segments
Revenue	71,655	81,982
Adjusted gross profit	40,044	47,655
Total assets	399,684		406,274
Permian Basin | Operating Segments
Business segments
Revenue	49,131	52,712
Adjusted gross profit	26,784	32,594
Total assets	302,732		305,701
Bakken Basin | Operating Segments
Business segments
Revenue	4,185	4,772
Adjusted gross profit	1,404	1,635
Total assets	57,764		59,134
Government | Operating Segments
Business segments
Revenue	16,592	16,555
Adjusted gross profit	11,580	11,851
Total assets	33,233		35,484
All Other
Business segments
Total assets	5,955		5,955
All Other | Operating Segments
Business segments
Revenue	1,747	7,943
Adjusted gross profit	276	$ 1,575
Total assets	$ 5,955		$ 5,955