Goodwill and Intangible Assets - Goodwill (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2021	Dec. 31, 2020
Goodwill And Intangible Assets Disclosure [Abstract]
Beginning balance, Goodwill Gross Carrying Amount	$ 1,211.8	$ 1,202.8
Foreign currency translation, Gross Carrying Amount	(2.7)	9.0
Ending balance, Goodwill Gross Carrying Amount	1,209.1	1,211.8
Beginning balance, Accumulated Impairment Loss	(145.4)	(144.3)
Impairment of goodwill, Accumulated Impairment Loss		(1.1)
Ending balance, Accumulated Impairment Loss	(145.4)	(145.4)
Beginning balance, Goodwill Net	1,066.4	1,058.5
Foreign currency translation, Net	(2.7)	9.0
Ending balance, Goodwill Net	$ 1,063.7	$ 1,066.4

Goodwill translation adjustments gross.

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
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- References

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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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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