Long-Term Obligations - Summary of Long-Term Obligations (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debt obligations less unamortized discount and debt issuance costs	$ 894,030	$ 811,097
Capital lease obligations and other debt	58,539	55,244
Long-term debt and capital lease obligations, including current maturities	952,569	866,341
Less — current portion	(33,947)	(33,623)
Current potion of long-term debt	918,622	832,718
Revolving line of credit [Member]
Debt Instrument [Line Items]
Principal amount	322,000	232,000
Less unamortized debt issuance costs	3,470	3,725
Debt obligations less unamortized discount and debt issuance costs	$ 318,530	$ 228,275
Effective interest rate (percentage)	1.96%	1.92%
Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount	$ 577,500	$ 585,000
Less unamortized debt issuance costs	2,230	2,408
Debt obligations less unamortized discount and debt issuance costs	$ 575,270	$ 582,592
Effective interest rate (percentage)	1.94%	1.92%
Secured Seller Notes [Member]
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
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-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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-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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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
-Name Accounting Standards Codification
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-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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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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-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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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