CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Net income	$ 23,138	$ 25,924	$ 50,091	$ 49,487
Other comprehensive income, net of tax:
Foreign currency translation adjustments	311	217	(41)	(119)
Unrealized cash flow hedge gains (losses) arising during the period	(1,949)	(632)	(3,576)	1,534
Net (gains) losses reclassified into income for revenue hedges	128	(1,158)	144	(3,019)
Net (gains) losses reclassified into income for cost of revenues hedges	26	93	(239)	290
Net unrealized gains (losses) on cash flow hedges	(1,795)	(1,697)	(3,671)	(1,195)
Unrealized holding gains (losses) during the period	164	46	6	58
Other comprehensive income (loss)	(1,320)	(1,434)	(3,706)	(1,256)
Comprehensive income	$ 21,818	$ 24,490	$ 46,385	$ 48,231