Guarantees, Other Contingent Liabilities, And Other Matters Guarantees, Other Contingent Liabilities, And Other Matters (Repurchases of Common and Preferred Stock) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Common stock
Repurchases of Common and Preferred Stock [Line Items]
Number of shares repurchased	479,688	238,486
Cost of shares repurchased (in thousands of dollars)	$ 21,553	$ 14,145
Weighted-average cost per share	$ 44.93	$ 59.31
Series B 6.75% convertible perpetual preferred stock
Repurchases of Common and Preferred Stock [Line Items]
Number of shares repurchased	403	0
Cost of shares repurchased (in thousands of dollars)	$ 408	$ 0
Weighted-average cost per share	$ 1,012.22	$ 0