Long-Term Obligations - Summary of Long-Term Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debt obligations less unamortized discount and debt issuance costs	$ 1,207,628	$ 811,097
Capital lease obligations and other debt	71,006	55,244
Long-term debt and capital lease obligations, including current maturities	1,278,634	866,341
Less — current portion	(32,512)	(33,623)
Current potion of long-term debt	1,246,122	832,718
Revolving credit
Debt Instrument [Line Items]
Principal amount	340,000	232,000
Less unamortized debt issuance costs	(4,321)	(3,725)
Debt obligations less unamortized discount and debt issuance costs	$ 335,679	$ 228,275
Effective interest rate (percentage)	2.31%	1.92%
Senior term notes
Debt Instrument [Line Items]
Principal amount	$ 874,500	$ 585,000
Less unamortized debt issuance costs	(2,781)	(2,408)
Debt obligations less unamortized discount and debt issuance costs	$ 871,719	$ 582,592
Effective interest rate (percentage)	2.27%	1.92%
Secured seller note
Debt Instrument [Line Items]
Debt obligations less unamortized discount and debt issuance costs	$ 230	$ 230
Stated interest rate (percentage)	10.00%	10.00%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer.

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Amount of long-term debt and capital lease obligations including current maturities.

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Capital Debt Obligations and Other Borrowings

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