Other Financial Statement Details - Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 2,945.7	$ 2,644.1
Less accumulated depreciation and amortization	1,949.0	1,876.2
Total property, plant and equipment, net	996.7	767.9
Depreciation	180.6	123.7	$ 122.9
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	83.4	73.4
Building and building improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	647.6	508.5
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	2,095.5	1,943.9
Projects in process
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross	$ 119.2	$ 118.3

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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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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