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Line of Credit, Long-Term Debt and Capital Lease Obligations - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Debt Instrument [Line Items] |  |
Debt instrument principal amount | $ 1,713,500 | $ 1,283,500
Less: Current portion, principal | (20,000) | (10,000)
Debt instrument principal long-term portion | 1,693,500 | 1,273,500
Unamortized debt issuance cost | (11,368) | (13,096)
Less: Current portion, unamortized debt issuance costs | 0 | 0
Long-term portion, principal, unamortized debt issuance costs | (11,368) | (13,096)
Long term debt | 1,702,132 | 1,270,404
Less: Current portion | (20,000) | (10,000)
Long-term portion | 1,682,132 | 1,260,404
5.25% Senior Unsecured Notes Due 2023 [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument principal amount | 750,000 | 750,000
Unamortized debt issuance cost | (11,109) | (12,695)
Long term debt | 738,891 | 737,305
Revolving Credit Facility [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument principal amount | 783,500 | 343,500
Long term debt | 783,500 | 343,500
Term Loan Credit Facility [Member] |  |
Debt Instrument [Line Items] |  |
Debt instrument principal amount | 180,000 | 190,000
Unamortized debt issuance cost | (259) | (401)
Long term debt | $ 179,741 | $ 189,599

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- Definition 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. + References 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 -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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