Interest Paid in Cash Including Payments Related to Derivative Contracts (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract]
Interest paid in cash including payments related to derivative contracts	$ 25.0	$ 20.7	$ 72.5	$ 65.6