Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Sep. 30, 2019	Mar. 31, 2019
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 1,301.4	$ 1,304.7
Less: accumulated depreciation	(835.7)	(820.0)
Net property, plant and equipment	465.7	484.7
Land [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	20.1	20.7
Buildings and Improvements [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 281.6	$ 285.9
Buildings and Improvements [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	10 years	10 years
Buildings and Improvements [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	40 years	40 years
Machinery and Equipment [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 863.9	$ 848.7
Machinery and Equipment [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	3 years	3 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	15 years	15 years
Office Equipment [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 93.5	$ 92.0
Office Equipment [Member] \| Minimum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	3 years	3 years
Office Equipment [Member] \| Maximum [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Property, plant and equipment, depreciable lives	10 years	10 years
Construction in Progress [Member]
Property, plant and equipment, including depreciable lives [Abstract]
Gross property, plant and equipment	$ 42.3	$ 57.4

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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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 1
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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- References

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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.

+ References

No definition available.

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