The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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

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

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Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Intangible Assets (Details) - USD ($) $ in Millions	Jun. 30, 2024	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2023
Intangible Assets [Abstract]
Gross carrying value		$ 231.1	$ 245.8
Accumulated amortization		(84.4)	(57.5)
Net intangible assets		146.7	188.3
Amortization expense		27.4	9.2	$ 8.0
Estimated Future Amortization Expense [Abstract]
Fiscal 2026		17.0
Fiscal 2027		15.0
Fiscal 2028		15.0
Fiscal 2029		15.0
Fiscal 2030		14.0
Customer Relationships [Member]
Intangible Assets [Abstract]
Gross carrying value		145.4	150.5
Accumulated amortization		(47.5)	(26.3)
Net intangible assets		97.9	124.2
Trade Names [Member]
Intangible Assets [Abstract]
Gross carrying value		53.1	62.8
Accumulated amortization		(21.2)	(18.5)
Net intangible assets		31.9	44.3
Trade Names [Member] \| Scott Springfield Manufacturing
Intangible Assets [Abstract]
Measurement period adjustment to intangible asset	$ (9.6)
Acquired Technology [Member]
Intangible Assets [Abstract]
Gross carrying value		32.6	32.5
Accumulated amortization		(15.7)	(12.7)
Net intangible assets		$ 16.9	$ 19.8