Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Amortized intangible assets [Abstract]
Gross carrying value	$ 142.7	$ 144.3
Accumulated amortization	(36.4)	(28.1)
Net intangible assets	106.3	116.2
Amortization expense	8.9	9.0	$ 9.7
Estimated future amortization expense [Abstract]
Fiscal 2021	8.4
2022	8.0
2023	8.0
2024	8.0
2025	8.0
BHVAC [Member]
Estimated future amortization expense [Abstract]
Impairment charges			$ 1.2
Customer Relationships [Member]
Amortized intangible assets [Abstract]
Gross carrying value	60.8	61.5
Accumulated amortization	(12.6)	(9.1)
Net intangible assets	48.2	52.4
Trade Names [Member]
Amortized intangible assets [Abstract]
Gross carrying value	58.3	58.9
Accumulated amortization	(16.2)	(13.5)
Net intangible assets	42.1	45.4
Acquired Technology [Member]
Amortized intangible assets [Abstract]
Gross carrying value	23.6	23.9
Accumulated amortization	(7.6)	(5.5)
Net intangible assets	$ 16.0	$ 18.4

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

+ References

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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