Interest and Other Income (Expense), net (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012
Interest income (expense), net
Interest income	$ 1,831	$ 2,215	$ 3,121
Interest expense	(2,228)	(1,308)	(447)
Interest income (expense), net	(397)	907	2,674
Other income (expense), net
Investment income related to deferred compensation plan	1,487	933	227
Gain on sale of securities		831	6,109
Impairment of investments	(624)	(3,600)
Foreign currency exchange gain, net	62	104	1,575
Other	1,068	(466)	(256)
Other income (expense), net	$ 1,993	$ (2,198)	$ 7,655