Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net (loss) income	$ (145,351)	$ 87,910	$ 65,981
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation, accretion, and amortization of intangible assets	179,902	127,775	123,829
Amortization of deferred financing costs and note discount	12,574	11,529	11,363
Share-based compensation expense	14,395	21,430	19,454
Deferred income tax (benefit) expense	(16,298)	9,886	10,993
Loss (gain) on disposal and impairment of assets	33,275	81	(14,010)
Other reserves and non-cash items	5,055	1,901	3,145
Goodwill and intangible asset impairment	194,521
Changes in assets and liabilities:
Decrease (increase) in accounts and notes receivable, net	6,616	(16,284)	17,384
Increase in prepaid expenses, deferred costs, and other current assets	(18,679)	(12,491)	(19,588)
Increase in inventory, net	(1,673)	(1,191)	(4,668)
Increase in other assets	(24,934)	(21,955)	8,415
(Decrease) increase in accounts payable	(24,938)	15,468	(8,016)
Increase in accrued liabilities	1,830	46,508	31,889
Increase (decrease) in other liabilities	1,597	(292)	10,382
Net cash provided by operating activities	217,892	270,275	256,553
Cash flows from investing activities:
Additions to property and equipment	(144,140)	(125,882)	(142,349)
Acquisitions, net of cash acquired	(487,077)	(22,669)	(103,874)
Proceeds from sale of assets and businesses		9,348	36,661
Net cash used in investing activities	(631,217)	(139,203)	(209,562)
Cash flows from financing activities:
Proceeds from borrowings under revolving credit facility	1,081,689	235,368	452,670
Repayments of borrowings under revolving credit facility	(976,161)	(311,362)	(499,551)
Proceeds from borrowings of long-term debt	300,000
Debt issuance costs	(5,704)
Tax payments related to share-based compensation	(8,504)
Proceeds from exercises of stock options	104	673	1,107
Additional tax benefit related to share-based compensation		338	1,985
Repurchase of common shares		(3,959)	(4,731)
Net cash provided by (used in) financing activities	391,424	(78,942)	(48,520)
Effect of exchange rate changes on cash	(263)	(4,893)	(4,049)
Net (decrease) increase in cash and cash equivalents	(22,164)	47,237	(5,578)
Cash and cash equivalents as of beginning of period	73,534	26,297	31,875
Cash and cash equivalents as of end of period	51,370	73,534	26,297
Supplemental disclosure of cash flow information:
Cash paid for interest	31,649	16,718	19,494
Cash paid for income taxes	$ 6,367	$ 17,886	$ 28,292