Long-Term Debt and Short-Term Borrowings - Schedule of Long-Term Debt (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total long-term debt	$ 1,772,688	$ 2,022,598
Less: current maturities of long-term debt	(51)	(8)
Less: unamortized debt issuance costs	(14,449)	(22,987)
Total long-term debt, net of current maturities	1,758,188	1,999,603
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Total long-term debt	51	8
2.51% to 2.91% Senior Term Loans [Member] \| Senior secured term loans [Member]
Debt Instrument [Line Items]
Total long-term debt	750,000	200,000
4.875% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	596,366	596,273
5.00% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt		800,000
5.25% Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Total long-term debt	$ 426,271	$ 426,317

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
-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

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