CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Mar. 31, 2013
Current assets:
Cash and cash equivalents	$ 71,446	$ 54,910
Short-term investments	14,447	23,354
Receivables (net of allowances of $210 at September 30, 2013 and $319 at March 31, 2013)	35,127	40,005
Inventories	27,368	26,786
Prepaid expenses and other current assets	5,808	3,319
Net deferred tax assets, current	4,909	4,589
Total current assets	159,105	152,963
Long-term investments	17,969	17,000
Investment in unconsolidated affiliate	2,629	2,613
Property and equipment, net	25,859	25,330
Intangible assets, net	2,373	3,122
Net deferred tax assets, non-current	649	643
Other assets	81	92
Total assets	208,665	201,763
Current liabilities:
Accounts payable	7,001	8,123
Accrued payroll and related expenses	5,507	6,261
Accrued taxes	433	440
Other accrued liabilities	2,378	2,838
Deferred revenue	1,235	1,362
Warranty reserve	872	995
Total current liabilities	17,426	20,019
Non-current liabilities:
Deferred rent	751	729
Deferred revenue	4,412	3,750
Warranty reserve	741	389
Notes payable, less current portion	632	682
Total non-current liabilities	6,536	5,550
Total liabilities	23,962	25,569
Commitments and contingencies (Note 9)
Shareholders' equity:
Preferred stock, no par value: 5,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, no par value: 35,000,000 shares authorized; 22,320,000 and 22,120,000 shares issued and outstanding at September 30, 2013 and at March 31, 2013, respectively	122,311	121,019
Retained earnings	62,358	55,133
Accumulated other comprehensive income	34	42
Total shareholders' equity	184,703	176,194
Total liabilities and shareholders' equity	$ 208,665	$ 201,763