Risks, Uncertainties, Contingencies and Litigation (Details) - USD ($) $ in Millions	Jun. 30, 2025	Mar. 31, 2025
Risks, Uncertainties, Contingencies and Litigation
Reserves for environmental matters	$ 15.0	$ 15.8
Purchase commitments	$ 35.0

Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 450
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483076/450-20-50-1

Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
-SubTopic 30
-Name Accounting Standards Codification
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-Paragraph 10
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-URI https://asc.fasb.org/1943274/2147481931/410-30-50-10

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 410
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481931/410-30-50-10

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 410
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-URI https://asc.fasb.org/1943274/2147481899/410-30-55-16

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 450
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Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant