Debt - Summary of Outstanding Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Total debt	$ 1,219,250	$ 1,224,375
Less: current portion	170,500	20,500
Total long-term debt, gross (less current portion)	1,048,750	1,203,875
Total long-term debt, gross (less current portion)	1,048,750	1,203,875
Less: deferred financing costs, net	12,499	13,318
Total long-term debt, net (less current portion)	1,036,251	1,190,557
Bank Credit Facility [Member]
Debt Instrument [Line Items]
Total debt	1,019,250	1,024,375
5 1/2% Senior Notes Due 2021 [Member]
Debt Instrument [Line Items]
Total debt	$ 200,000	$ 200,000

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.

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-Name Accounting Standards Codification
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-Section 50
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

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

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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