Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows From Operating Activities:
Net income (loss)	$ 55,841	$ (181,945)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Goodwill impairment charges		269,332
Depreciation and amortization	119,635	120,597
Amortization of debt issuance costs and discounts	3,460	3,611
Loss on early extinguishment of debt and write-off of discounts and debt issuance costs		8,143
Loss on sale or disposal of assets, net	12,477	9,353
Deferred benefit from income tax	24,478	(74,437)
Equity-based compensation	18,620	19,265
Changes in assets and liabilities:
Accounts receivable	(36,806)	(17,448)
Inventories	(3,374)	(4,233)
Prepaid expenses and other current assets	2,866	6,452
Accounts payable and accrued expenses	8,649	5,327
Accrued salaries, wages and benefits	10,225	1,406
Deferred revenue	36,586	19,867
Other accrued liabilities	14,902	(451)
Other assets and liabilities	(101)	2,940
Net cash provided by operating activities	267,458	187,779
Cash Flows From Investing Activities:
Capital expenditures	(140,878)	(139,638)
Other investing activities	(349)	1,515
Net cash used in investing activities	(141,227)	(138,123)
Cash Flows From Financing Activities:
Proceeds from issuance of debt		998,306
Repayments of long-term debt	(17,780)	(1,020,983)
Proceeds from draw on revolving credit facility	55,000	80,649
Repayments of revolving credit facility	(70,000)	(105,000)
Debt issuance costs		(15,390)
Dividends paid to stockholders	(325)	(1,535)
Payment of tax withholdings on equity-based compensation through shares withheld	(2,942)	(1,613)
Exercise of stock options	3,191	11
Net cash used in financing activities	(32,856)	(65,555)
Change in Cash and Cash Equivalents, including Restricted Cash	93,375	(15,899)
Cash and Cash Equivalents, including Restricted Cash—Beginning of period	33,997	69,378
Cash and Cash Equivalents, including Restricted Cash—End of period	127,372	53,479
Supplemental Disclosures of Noncash Investing and Financing Activities
Capital expenditures in accounts payable	23,125	19,835
Dividends declared, but unpaid	$ 101	$ 505