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Derivatives and Hedging Activity - Summary of Notional and Fair Values of Derivative Instruments (Detail) - USD ($)		Sep. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Notional Amount		$ 929,700,000	$ 901,400,000
Derivatives Assets		7,400,000	9,600,000
Derivative Liabilities		93,300,000	25,800,000
Other noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives Assets		5,800,000	5,700,000
Other noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		9,500,000	7,900,000
Interest Rate Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amount		900,000,000.0	850,000,000.0
Interest Rate Contracts [Member] | Other current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives Assets		0	3,000,000.0
Interest Rate Contracts [Member] | Accrued compensation and other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		43,700,000	13,000,000.0
Interest Rate Contracts [Member] | Other noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities		33,100,000
Foreign Exchange Contracts [Member]
Derivatives, Fair Value [Line Items]
Notional Amount	[1]	29,700,000	51,400,000
Foreign Exchange Contracts [Member] | Other current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivatives Assets	[1]	1,600,000	900,000
Foreign Exchange Contracts [Member] | Accrued compensation and other current liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liabilities	[1]	$ 7,000,000.0	$ 4,900,000
[1] Included within foreign exchange contracts at September 30, 2019 were $304.9 million of call options offset with $304.9 million of put options, and $22.2 million of buy forwards offset with $51.9 million of sell forwards. Included within foreign exchange contracts at December 31, 2018 were $276.4 million of call options offset with $276.4 million of put options, and $23.1 million of buy forwards offset with $72.9 million of sell forwards.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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