Supplemental Guarantor Financial Information - Cash Flows (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities			$ 84,579	$ 124,587
Additions to property and equipment	$ (31,307)	$ (23,120)	(69,868)	(39,571)
Acquisitions, net of cash acquired			(487,077)	(14,544)
Proceeds from sale of assets and businesses				9,348
Net cash used in investing activities			(556,945)	(44,767)
Proceeds from borrowings under revolving credit facility			835,505	134,307
Repayments of borrowings under revolving credit facility			(666,256)	(216,000)
Proceeds from borrowings of long-term debt			300,000
Debt issuance costs			(5,197)
Tax payments related to share-based compensation			(7,820)
Proceeds from exercises of stock options			105	145
Additional tax (expense) related to share-based compensation				(343)
Repurchase of common shares				(3,959)
Net cash provided by (used in) financing activities			456,337	(85,850)
Effect of exchange rate changes on cash			(4,328)	(615)
Net decrease in cash and cash equivalents			(20,357)	(6,645)
Cash and cash equivalents as of beginning of period			73,534	26,297
Cash and cash equivalents as of end of period	53,177	19,652	53,177	19,652
Parent [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities			8,017
Tax payments related to share-based compensation			(7,820)
Proceeds from exercises of stock options			105
Net cash provided by (used in) financing activities			(7,715)
Net decrease in cash and cash equivalents			302
Cash and cash equivalents as of beginning of period			101
Cash and cash equivalents as of end of period	403		403
Issuer | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities			14,322	48,940
Proceeds from borrowings under revolving credit facility			218,000	120,100
Repayments of borrowings under revolving credit facility			(232,100)	(182,700)
Intercompany financing				17,911
Proceeds from exercises of stock options				145
Additional tax (expense) related to share-based compensation				(343)
Repurchase of common shares				(3,959)
Net cash provided by (used in) financing activities			(14,100)	(48,846)
Net decrease in cash and cash equivalents			222	94
Cash and cash equivalents as of beginning of period			7	782
Cash and cash equivalents as of end of period	229	876	229	876
Guarantors [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities			57,477	28,784
Additions to property and equipment			(43,613)	(17,520)
Acquisitions, net of cash acquired			(467,598)	(14,544)
Net cash used in investing activities			(511,211)	(32,064)
Proceeds from borrowings under revolving credit facility			586,778
Repayments of borrowings under revolving credit facility			(417,279)
Proceeds from borrowings of long-term debt			300,000
Debt issuance costs			(5,197)
Intercompany financing			(3,217)
Net cash provided by (used in) financing activities			461,085
Effect of exchange rate changes on cash			(2,298)	(861)
Net decrease in cash and cash equivalents			5,053	(4,141)
Cash and cash equivalents as of beginning of period			6,995	6,200
Cash and cash equivalents as of end of period	12,048	2,059	12,048	2,059
Non-Guarantors [Member] | Reportable Legal Entities [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by operating activities			4,763	46,863
Additions to property and equipment			(26,255)	(22,051)
Acquisitions, net of cash acquired			(19,479)
Proceeds from sale of assets and businesses				9,348
Net cash used in investing activities			(45,734)	(12,703)
Proceeds from borrowings under revolving credit facility			30,727	14,207
Repayments of borrowings under revolving credit facility			(16,877)	(33,300)
Intercompany financing			3,217	(17,911)
Net cash provided by (used in) financing activities			17,067	(37,004)
Effect of exchange rate changes on cash			(2,030)	246
Net decrease in cash and cash equivalents			(25,934)	(2,598)
Cash and cash equivalents as of beginning of period			66,431	19,315
Cash and cash equivalents as of end of period	$ 40,497	$ 16,717	$ 40,497	$ 16,717