Derivatives And Hedging Activities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2011 Settled On Maturity [Member]	Dec. 31, 2011 Settled Prior To Maturity [Member]	Jun. 30, 2011 Fair Value Hedges [Member]
Derivative [Line Items]
Notional amount of interest rate fair value hedge derivatives			$ 50	$ 195	$ 245
Aggregate gain on the termination of interest rate swap agreements		13
Notional amount of interest rate cash flow hedge derivatives	95
Cash flow hedge loss to be reclassified within twelve months	1.1
Net unrealized loss on foreign currency derivatives designated as cash flow hedges	$ 0.2