Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 1,304.7	$ 1,302.2
Less: accumulated depreciation	(820.0)	(797.9)
Net property, plant and equipment	484.7	504.3
Depreciation expense	67.9	67.0	$ 54.2
Loss from disposition of property, plant and equipment	(0.9)	(0.7)	$ (0.4)
Land [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	20.7	22.6
Buildings and Improvements [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 285.9	295.6
Buildings and Improvements [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	10 years
Buildings and Improvements [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	40 years
Machinery and Equipment [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 848.7	840.8
Machinery and Equipment [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	15 years
Office Equipment [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 92.0	93.0
Office Equipment [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	3 years
Office Equipment [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	10 years
Construction in Progress [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 57.4	$ 50.2