Income Tax Expense (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income Tax [Line Items]
Federal, Current	$ 38,480	$ 30,459	$ 24,232
State, Current	5,684	3,778	2,736
Foreign, Current	19,438	16,282	14,114
Total current	63,602	50,519	41,082
Federal, Deferred	3,915	(1,609)	(1,358)
State, Deferred	214	(962)	2,010
Foreign, Deferred	(2,456)	(656)	(3,716)
Total deferred	1,673	(3,227)	(3,064)
Income tax expense	$ 65,275	$ 47,292	$ 38,018