Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Mar. 31, 2012
Current assets:
Cash and cash equivalents	$ 79,838	$ 97,587
Accounts receivable, net of allowances of $759 and $632, respectively	51,923	32,531
Inventories	18,192	15,710
Prepaid expenses	2,863	2,975
Other current assets	1,538	5,492
Total current assets	154,354	154,295
Property and equipment, net	15,231	16,504
Goodwill	14,259	15,198
Intangible assets, net	15,922	14,135
Other non-current assets	4,005	4,007
Total assets	203,771	204,139
Current liabilities:
Accounts payable	42,298	24,938
Deferred revenue	23,717	28,441
Accrued liabilities	13,428	23,983
Capital lease obligations, current	342	647
Total current liabilities	79,785	78,009
Deferred income taxes, non-current	5,186	5,135
Capital lease obligations, non-current	428	347
Other non-current liabilities	5,151	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 22,136,981 and 21,875,850 shares outstanding and December 31, 2012 and March 31, 2012, respectively	9,482	9,482
Treasury shares, 9,469,850 and 9,730,981 at December 31, 2012 and March 31, 2012, respectively	(2,840)	(2,919)
Capital in excess of stated value	(14,919)	(16,032)
Retained earnings	122,248	123,876
Accumulated other comprehensive (loss) income	(750)	31
Total shareholders' equity	113,221	114,438
Total liabilities and shareholders' equity	$ 203,771	$ 204,139