Interest Expense, Net (Schedule of Interest Expense, Net) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Interest Expense [Abstract]
Interest expense	$ 70,077	$ 68,846	$ 62,719
Interest and finance charge (income)	(2,583)	(2,509)	(2,665)
Interest expense, net	$ 67,494	$ 66,337	$ 60,054