Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Current assets:
Cash and cash equivalents	$ 20,916	$ 9,451
Short-term marketable securities	55,663	67,256
Accounts receivable, net	24,357	22,946
Inventories	13,948	14,930
Prepaid expenses and other current assets	3,082	2,022
Total current assets	117,966	116,605
Long-term marketable securities	41,761	11,406
Property and equipment, net	6,889	6,549
Goodwill	37,990	35,410
Other	801	29
Total assets	205,407	169,999
Current liabilities:
Accounts payable	7,746	7,696
Accrued expenses	17,899	15,162
Deferred revenue	4,766	4,198
Total current liabilities	30,411	27,056
Long-term deferred tax liability	6,415	5,554
Other long-term liabilities	228	309
Total liabilities	37,054	32,919
Commitments and contingencies
Stockholders' equity:
Class B Preferred Stock, $.01 par value Authorized-1,000,000 shares; Issued and outstanding-none
Common stock, $.01 par value Authorized-100,000,000 shares; Issued-41,122,695 shares at March 31, 2014 and 39,788,383 shares at March 31, 2013; Outstanding-39,916,328 shares at March 31, 2014 and 38,601,384 shares at March 31, 2013	411	397
Additional paid in capital	436,136	414,810
Accumulated deficit	(250,910)	(258,261)
Treasury stock at cost-1,206,367 shares at March 31, 2014 and 1,186,999 shares at March 31, 2013	(16,554)	(16,129)
Accumulated other comprehensive loss	(730)	(3,737)
Total stockholders' equity	168,353	137,080
Total liabilities and stockholders' equity	$ 205,407	$ 169,999