Total Revenue by Geography (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Total revenue	$ 91,567	$ 83,297	$ 252,473	$ 219,217
United States
Segment Reporting Information [Line Items]
Total revenue	66,990	60,737	188,701	162,273
Europe
Segment Reporting Information [Line Items]
Total revenue	12,940	9,278	31,373	24,117
Asia
Segment Reporting Information [Line Items]
Total revenue	4,201	4,839	12,678	13,314
Rest Of The World
Segment Reporting Information [Line Items]
Total revenue	$ 7,436	$ 8,443	$ 19,721	$ 19,513