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Derivative Instruments - Gain (Loss) on the Company's Foreign Currency Forward Contracts Recorded in the Consolidated Statements of Operations and Comprehensive Income (Details) - Foreign currency forward contracts - USD ($) $ in Millions | 12 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2019
Derivative [Line Items] |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | $ (4.5) | $ 0.5 | $ 4.7
Asbestos adjustments (gain) loss |  |  |
Derivative [Line Items] |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | (11.7) | (0.8) | 0.8
Selling, general and administrative expenses |  |  |
Derivative [Line Items] |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | $ 7.2 | $ 1.3 | $ 3.9

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + Details
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