Derivatives And Hedging Activities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Derivative [Line Items]
Notional amount of interest rate cash flow hedge derivatives	$ 93.0
Aggregate gain on the termination of interest rate swap agreements		13
Notional amount of foreign currency derivatives not designated as hedges related to net monetary assets and liabilities of foreign subsidiaries			60
Interest rate cash flow hedge gain (loss) to be reclassified during next 12 months, net	1
Net unrealized loss on foreign currency derivatives designated as cash flow hedges	0.8
Settled On Maturity [Member]
Derivative [Line Items]
Notional amount of interest rate fair value hedge derivatives		50
Settled Prior To Maturity [Member]
Derivative [Line Items]
Notional amount of interest rate fair value hedge derivatives		195
Fair Value Hedges [Member]
Derivative [Line Items]
Notional amount of interest rate fair value hedge derivatives			$ 245