Other Financial Statement Details - Property, Plant and Equipment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Mar. 31, 2020
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 3,038.4		$ 3,038.4		$ 2,966.1
Less accumulated depreciation and amortization	2,211.0		2,211.0		2,090.0
Total property, plant and equipment, net	827.4		827.4		876.1
Depreciation expense	40.3	$ 41.4	120.4	$ 127.1
Land
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	79.9		79.9		83.4
Building and building improvements
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	643.7		643.7		659.5
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	2,190.6		2,190.6		2,123.1
Projects in process
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 124.2		$ 124.2		$ 100.1