Financial Instruments (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Derivative Financial Instruments
Investment grade bonds	$ 10.2	$ 0.0
Cash
Derivative Financial Instruments
Deferred compensation, Rabbi Trust	5.9	6.6
Short-term Investments
Derivative Financial Instruments
Deferred compensation, Rabbi Trust	7.7	7.7
Foreign Exchange Forward \| Designated as Hedging Instrument
Derivative Financial Instruments
Fair value	1.7	5.0
Notional amount	$ 122.6	93.5
Foreign Exchange Forward \| Designated as Hedging Instrument \| Cash Flow Hedging \| Maximum
Derivative Financial Instruments
Maturity term	15 months
Foreign Exchange Forward \| Not Designated as Hedging Instrument
Derivative Financial Instruments
Fair value	$ 0.2	0.2
Notional amount	$ 131.7	$ 63.7
Foreign Exchange Forward \| Not Designated as Hedging Instrument \| Maximum
Derivative Financial Instruments
Maturity term	1 year

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-Paragraph 1
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Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements. Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

+ References

No definition available.

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- Definition

Fair value of the assets less the liabilities of a derivative or group of derivatives.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
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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

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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