Property, Plant and Equipment (Details) - USD ($) $ in Millions	Sep. 30, 2015	Mar. 31, 2015
Property, plant and equipment [Abstract]
Gross property, plant and equipment	$ 1,018.1	$ 994.8
Accumulated depreciation	(688.4)	(672.7)
Net property, plant and equipment	$ 329.7	$ 322.1