Common And Preferred Stock (Schedule Of Repurchases Of Shares) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Class of Stock [Line Items]
Number of shares repurchased	169,432	80,191	1,113,125
Cost of shares repurchased (in thousands of dollars)	$ 8,631	$ 3,488	$ 46,696
Weighted-average cost per share	$ 50.94	$ 43.49	$ 41.95