Fair value portion of assets, excluding financial assets, that lack physical substance, having a limited useful life.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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.

+ References

No definition available.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

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-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Other Intangible Assets, net - Summary of Impairment Analysis and Impairment Charge Recognized (Parenthetical) (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Aug. 31, 2020	Jun. 30, 2020
Finite Lived Intangible Assets [Line Items]
Carrying value	$ 56.6	$ 63.1
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Carrying value	18.0	19.0
Customer Relationships \| Multi-Period Earnings Method
Finite Lived Intangible Assets [Line Items]
Carrying value			$ 73.8
Fair value			4.6
Trade Names and Trademarks
Finite Lived Intangible Assets [Line Items]
Carrying value	0.5	0.7
Trade Names and Trademarks \| Royalty Savings Approach
Finite Lived Intangible Assets [Line Items]
Carrying value			3.4
Fair value			$ 0.5
Proprietary Know How
Finite Lived Intangible Assets [Line Items]
Carrying value	$ 2.7	$ 3.4
Proprietary Know How \| Multi-Period Excess Earnings Method
Finite Lived Intangible Assets [Line Items]
Carrying value				$ 7.6
Fair value				$ 3.9