Business Segment, Geographic Area, Product/Service Offerings and Significant Customer Information - Reconciliation of Segment Assets to Consolidated Total Assets (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting, Asset Reconciling Item [Line Items]
Consolidated total assets	$ 855.2	$ 803.2
Other current assets	98.0	106.3
Property, plant and equipment, net	238.2	241.9
Right-of-use asset	127.1	64.5
Other assets	42.9	47.5
Consolidated total assets	3,474.9	3,416.3
Segment Reconciling Items [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Cash and cash equivalents and short-term investments	503.4	524.0
Other current assets	98.0	106.3
Property, plant and equipment, net	238.2	241.9
Right-of-use asset	127.1	64.5
Goodwill and intangible assets, net	1,604.1	1,623.1
Other assets	48.9	53.3
Consolidated total assets	$ 3,474.9	$ 3,416.3

Segment assets.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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- Definition

Cash includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the customer may deposit additional funds at any time and effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid Investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Short-term investments, exclusive of cash equivalents, generally consist of marketable securities intended to be sold within one year (or the normal operating cycle if longer) and may include trading securities, available-for-sale securities, or held-to-maturity securities (if maturing within one year), as applicable.

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Carrying amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Goodwill is an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Intangible assets are assets, not including financial assets, lacking physical substance.

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No definition available.

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- Definition

Amount of lessee's right to use underlying asset under operating lease.

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Amount of current assets classified as other.

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Amount of noncurrent assets classified as other.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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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