Components of Interest Expense (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Interest expense, borrowings:
Interest expense	$ 20,658	$ 18,055	$ 40,579	$ 35,869
Capitalized interest	(220)	(128)	(387)	(270)
Amortization of transaction costs	801	843	1,554	1,694
Interest expense resulting from derivatives	3,638	4,348	7,279	9,153
Total interest expense	24,877	23,118	49,025	46,446
Write-off of transaction costs related to early extinguishment of debt	298		298
Fees On Early Extinguishment Of Debt	3,783		3,783
Fees And Amortization On Early Extinguishment Of Debt	4,081		4,081
Total	$ 28,958	$ 23,118	$ 53,106	$ 46,446