Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Income Statement [Abstract]
Net revenues	$ 50,272	$ 54,148
Cost of revenues	20,257	22,342
Gross profit	30,015	31,806
Operating expenses:
Research and development	33,205	34,506
Selling, general and administrative	9,058	9,526
Gain on sale of TPack	0	(19,699)
Amortization of purchased intangible assets	62	130
Restructuring charges	1,211	93
Total operating expenses	43,536	24,556
Operating (loss) income	(13,521)	7,250
Interest income, net	336	3,666
Other (expense) income, net	(21)	129
(Loss) income before income taxes	(13,206)	11,045
Income tax (benefit) expense	(141)	188
Net (loss) income	$ (13,065)	$ 10,857
Basic net (loss) income per share	$ (0.17)	$ 0.16
Shares used in calculating basic net (loss) income per share	77,916	69,360
Diluted net (loss) income per share	$ (0.17)	$ 0.15
Shares used in calculating diluted (loss) income per share	77,916	70,234