Debt - Schedule of Debt (Detail) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Debt Instrument [Line Items]
Long-term debt, Gross	$ 3,999,750,000	$ 3,683,250,000
Less: Unamortized discount and debt issuance costs	(58,947,000)	(61,308,000)
Long-term debt	3,940,803,000	3,621,942,000
Senior secured term loan A facility
Debt Instrument [Line Items]
Senior secured term loan	277,500,000	292,500,000
Senior secured term loan B facility
Debt Instrument [Line Items]
Senior secured term loan	1,822,250,000	1,840,750,000
Senior secured revolving credit facility
Debt Instrument [Line Items]
Long-term debt	0	0
5.625% Senior Notes due 2024
Debt Instrument [Line Items]
Senior notes	1,050,000,000	1,050,000,000
Long-term debt, principal amount	$ 1,050,000,000
Long-term debt, interest rate (as a percent)	5.625%
4.50% Senior Notes due 2026
Debt Instrument [Line Items]
Senior notes	$ 500,000,000	500,000,000
Long-term debt, principal amount	$ 500,000,000
Long-term debt, interest rate (as a percent)	4.50%
4.50% Senior Notes due 2028
Debt Instrument [Line Items]
Senior notes	$ 350,000,000	$ 0
Long-term debt, principal amount	$ 350,000,000
Long-term debt, interest rate (as a percent)	4.50%

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
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

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- Definition

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

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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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No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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-Name Accounting Standards Codification
-Topic 835
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- Definition

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.

+ References

Reference 1: 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(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.9-03(16))
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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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