Goodwill and Intangible Assets - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill impairment			$ 3.3
Amortization of acquisition-related intangible assets	$ 120.3	$ 115.2	111.7
Intangible assets, net	469.0	590.5
IPRD
Finite-Lived Intangible Assets [Line Items]
IPRD projects reclassified to developed technology	15.2	23.2
Intangible assets, net	$ 24.1	$ 40.6
IPRD \| ISG
Finite-Lived Intangible Assets [Line Items]
Impairment of intangible assets			$ 3.5

Finite-lived Intangible Assets Reclassified

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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.

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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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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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