Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Mar. 31, 2012
Current assets:
Cash and cash equivalents	$ 80,336	$ 97,587
Accounts receivable, net of allowances of $609 and $632, respectively	34,656	32,531
Inventories	15,652	15,710
Prepaid expenses	3,188	2,975
Other current assets	1,790	5,492
Total current assets	135,622	154,295
Property and equipment, net	15,916	16,504
Goodwill	15,109	15,198
Intangible assets, net of amortization of $22,099 and $21,560, respectively	14,622	14,135
Other non-current assets	4,039	4,007
Total assets	185,308	204,139
Current liabilities:
Accounts payable	23,815	24,938
Deferred revenue	25,542	28,441
Accrued liabilities	11,224	23,983
Capital lease obligations, current	470	647
Total current liabilities	61,051	78,009
Deferred income taxes, non-current	5,152	5,135
Capital lease obligations, non-current	288	347
Other non-current liabilities	5,883	6,210
Commitments and contingencies (see Note 7)
Shareholders' equity:
Common shares, without par value, at $0.30 stated value; 80,000,000 shares authorized; 31,606,831 shares issued; and 22,104,245 and 21,875,850 shares outstanding and June 30, 2012 and March 31, 2012, respectively	9,482	9,482
Treasury shares, 9,502,586 and 9,730,981 at June 30, 2012 and March 31, 2012, respectively	(2,851)	(2,919)
Capital in excess of stated value	(15,720)	(16,032)
Retained earnings	122,083	123,876
Accumulated other comprehensive (loss) income	(60)	31
Total shareholders' equity	112,934	114,438
Total liabilities and shareholders' equity	$ 185,308	$ 204,139