CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Mar. 31, 2014
Current assets:
Cash and cash equivalents	$ 84,594	$ 73,589
Short-term investments	20,844	29,102
Receivables (net of allowances of $272 at September 30, 2014 and $182 at March 31, 2014)	36,351	29,227
Inventories	28,987	26,978
Prepaid expenses and other current assets	3,954	2,452
Net deferred tax assets, current	5,990	4,464
Total current assets	180,720	165,812
Long-term investments	20,851	18,491
Investment in unconsolidated affiliate	2,614	2,646
Property and equipment, net	28,884	27,176
Intangible assets, net	875	1,624
Net deferred tax assets, non-current	1,555	1,557
Other assets	131	74
Total assets	235,630	217,380
Current liabilities:
Accounts payable	10,143	6,111
Accrued payroll and related expenses	8,802	4,654
Accrued taxes	764	1,144
Other accrued liabilities	5,555	3,095
Deferred revenue	1,226	1,208
Warranty reserve	1,193	1,047
Total current liabilities	27,683	17,259
Non-current liabilities:
Deferred rent	768	768
Deferred revenue	3,576	4,035
Warranty reserve	992	821
Notes payable, less current portion	531	581
Total non-current liabilities	5,867	6,205
Total liabilities	33,550	23,464
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; 22,523,000 and 22,308,000 shares issued and outstanding at September 30, 2014 and at March 31, 2014, respectively	127,163	124,603
Retained earnings	74,935	69,318
Accumulated other comprehensive loss	(18)	(5)
Total shareholders' equity	202,080	193,916
Total liabilities and shareholders' equity	$ 235,630	$ 217,380