The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 2
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Amortizable Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Intangible assets, amortization expense	$ 69.9	$ 69.9	$ 54.8
Intangible assets, estimated amortization expense, 2017	69.9
Intangible assets, estimated amortization expense, 2018	68.4
Intangible assets, estimated amortization expense, 2019	68.4
Intangible assets, estimated amortization expense, 2020	68.3
Intangible assets, estimated amortization expense, 2021	$ 68.2
Customer Relationships and Platforms [Member] \| Weighted Average [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	12 years
Patented and Unpatented Technology [Member] \| Weighted Average [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	13 years
Trade Names and Trademarks [Member] \| Weighted Average [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets, useful life	15 years