Components of Interest Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Interest expense, borrowings:
Interest expense	$ 19,921	$ 17,814
Capitalized interest	(167)	(142)
Amortization of transaction costs	753	851
Interest expense resulting from derivatives	3,641	4,805
Total interest expense	$ 24,148	$ 23,328