Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net loss	$ (27,476)	$ (30,531)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities
Depreciation and amortization	27,498	30,235
Accretion on asset retirement obligation	85	41
Change in allowance for doubtful accounts	(265)	(159)
Amortization of deferred financing costs	564	176
Amortization of debt discounts	262	1,474
Non-cash compensation	3,288	6,798
Loss on disposal of assets	1,455	1,779
Deferred income taxes	0	(78)
Changes in operating assets and liabilities:
Accounts receivable	4,763	(7,618)
Inventories	2,709	(812)
Prepaid expenses and other current assets	(1,282)	1,593
Other assets	(549)	44
Accounts payable	(20,496)	(5,987)
Income tax receivable	(1,851)	19
Other liabilities	(2,559)	(1,641)
Accrued expenses	15,658	9,215
Net cash provided by operating activities	1,804	4,548
Cash flows from investing activities:
Purchase of property and equipment	(18,885)	(15,412)
Proceeds from sale of assets	2,664	198
Net cash used in investing activities	(16,221)	(15,214)
Cash flows from financing activities:
Proceeds from debt	0	21,000
Payments of debt	(11,423)	(13,657)
Change in treasury stock including restricted stock issuances	(343)	(1,342)
Deferred loan costs and other financing activities	(321)	0
Net cash provided by (used in) financing activities	(12,087)	6,001
Net decrease in cash and cash equivalents	(26,504)	(4,665)
Cash and cash equivalents - beginning of period	90,300	86,223
Cash and cash equivalents - end of period	63,796	81,558
Noncash investing and financing activity:
Finance leases and notes issued for equipment	6,144	3,321
Change in accrued property and equipment	(994)	2,518
Change in asset retirement obligations	124	58
Income tax paid	$ 0	$ 0