Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Cash flows from operating activities:
Net loss	$ (6,355)	$ (32,167)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	9,135	14,744
Amortization of debt issuance costs, net	206	0
Accrued interest added to debt principal	0	119
Stock-based compensation	852	10,978
Impairment of long-lived assets	117	4,131
Gain on sale of UGSI	0	(75)
Gain on disposal of property, plant and equipment	(858)	(8)
Bad debt (recoveries) expense	(141)	313
Change in fair value of derivative warrant liability	41	192	$ (443)
Deferred income taxes	70	0
Other, net	29	149
Changes in operating assets and liabilities:
Accounts receivable	2,944	(5,534)
Prepaid expenses and other receivables	(1,104)	(2,573)
Accounts payable and accrued liabilities	(6,735)	2,110
Other assets and liabilities, net	1,294	368
Net cash used in operating activities	(505)	(7,253)
Cash flows from investing activities:
Proceeds from the sale of property, plant and equipment	3,665	11,881
Purchases of property, plant and equipment	(3,626)	(3,380)
Proceeds from the sale of UGSI	0	75
Net cash provided by investing activities	39	8,576
Cash flows from financing activities:
Payments on First and Second Lien Term Loans	(1,102)	(799)
Proceeds from Revolving Facility	51,037	55,321
Payments on Revolving Facility	(51,037)	(56,001)
Payments on Bridge Term Loan	(31,382)	0
Proceeds from the issuance of stock	31,057	0
Payments on finance leases and other financing activities	(787)	(456)
Net cash used in financing activities	(2,214)	(1,935)
Change in cash and restricted cash	(2,680)	(612)
Cash, beginning of period	7,302	5,488	5,488
Restricted cash, beginning of period	656	1,296	1,296
Cash and restricted cash, beginning of period	7,958	6,784	6,784
Cash, end of period	3,949	4,088	7,302
Restricted cash, end of period	1,329	2,084	656
Cash and restricted cash, end of period	5,278	6,172	$ 7,958
Supplemental disclosure of cash flow information:
Cash paid for interest	1,205	951
Cash paid for taxes, net	0	52
Common stock issued to settle Bridge Term Loan	$ 1,118	$ 0