Lease Obligations - Schedule of future minimum lease payments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Finance Lease Obligations
Remainder of 2019	$ 592
2020	1,185
2021	346
2022	0
2023	0
Thereafter	0
Total minimum lease payments	2,123
Financing component	(65)
Net present value of minimum lease payments	2,058
Less: current portion of finance and operating lease obligations	(1,135)	$ (1,119)
Long-term finance and operating lease obligations	923	1,514
Operating Lease Obligations
Remainder of 2019	2,911
2020	4,481
2021	3,674
2022	2,830
2023	1,534
Thereafter	2,480
Total minimum lease payments	17,910
Financing component	(3,637)
Net present value of minimum lease payments	14,273
Less: current portion of finance and operating lease obligations	(3,817)	0
Long-term finance and operating lease obligations	10,456	$ 0
Total Lease Obligations
Remainder of 2019	3,503
2020	5,666
2021	4,020
2022	2,830
2023	1,534
Thereafter	2,480
Total minimum lease payments	20,033
Financing component	(3,702)
Net present value of minimum lease payments	16,331
Less: current portion of finance and operating lease obligations	(4,952)
Long-term finance and operating lease obligations	$ 11,379