Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flows From Operating Activities:
Net loss	$ (37,020)	$ (62,844)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	39,450	38,430
Amortization of debt issuance costs and discounts	899	1,157
Loss on sale or disposal of assets, net	45	396
Deferred income tax benefit	(16,606)	(23,817)
Equity-based compensation	3,198	7,545
Changes in assets and liabilities:
Accounts receivable	(2,329)	(21,218)
Inventories	(6,964)	(6,761)
Prepaid expenses and other current assets	(628)	(3,141)
Right of use assets-operating	1,189
Accounts payable and accrued expenses	1,715	16,540
Accrued salaries, wages and benefits	(1,737)	5,729
Deferred revenue	51,697	62,162
Other accrued liabilities	5,498	5,879
Operating lease obligations	(1,061)
Other assets and liabilities	342	260
Net cash provided by operating activities	37,688	20,317
Cash Flows From Investing Activities:
Capital expenditures	(47,937)	(45,822)
Other investing activities	50
Net cash used in investing activities	(47,887)	(45,822)
Cash Flows From Financing Activities:
Repayments of long-term debt	(3,877)	(5,927)
Proceeds from draws on revolving credit facility	55,000	45,000
Repayments of revolving credit facility	(20,000)	(5,000)
Dividends paid to stockholders	(58)	(287)
Payment of tax withholdings on equity-based compensation through shares withheld	(3,606)	(1,634)
Exercise of stock options	715	7
Other financing activities	(168)
Net cash provided by financing activities	28,006	32,159
Change in Cash and Cash Equivalents, including Restricted Cash	17,807	6,654
Cash and Cash Equivalents, including Restricted Cash—Beginning of period	35,007	33,997
Cash and Cash Equivalents, including Restricted Cash—End of period	52,814	40,651
Supplemental Disclosures of Noncash Investing and Financing Activities
Capital expenditures in accounts payable	49,620	32,744
Dividends declared, but unpaid	$ 23	$ 136