Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification

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For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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The increase (decrease) during the reporting period in other noncurrent operating liabilities not separately disclosed in the statement of cash flows.

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No definition available.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Business Acquisitions (Additional Information) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2013	Sep. 30, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High			$ 17.4
Goodwill		141.6
Identifiable intangible assets		134.5
Weighted average life		10 years 2 months
Business Combination Acquisition Related Adjustments	7.7
Other Acquisitions [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Purchase Price, Total		$ 258.3