CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Mar. 31, 2012
Current assets:
Cash and cash equivalents	$ 40,418	$ 24,369
Restricted cash	12,618	11,707
Short-term investments, at fair value	108,546	170,834
Accounts receivable, net of allowances of $351 at March 31, 2013 and $255 at March 31, 2012	28,477	25,439
Unbilled costs and fees	4,875	3,206
Inventories	48,051	48,179
Prepaid expenses and other current assets	8,829	10,386
Deferred income taxes	3,155	3,329
Total current assets	254,969	297,449
Building, equipment and leasehold improvements, net	16,451	17,998
Restricted cash	899	4,183
Deferred income taxes	8,325	5,174
Other assets, net	805	61
Total assets	281,449	324,865
Current liabilities:
Accounts payable	8,371	7,461
Accrued salaries and benefits	9,974	11,722
Accrued warranty costs	397	358
Accrued income taxes	2,094
Deferred revenue	15,770	16,731
Customer deposits	16,199	15,031
Current portion of lease financing liability	1,489	1,351
Other current liabilities	14,194	5,989
Total current liabilities	68,488	58,643
Lease financing liability, net of current portion	2,914	4,403
Deferred revenue	5,535	2,913
Other long term liabilities	267	100
Total liabilities	77,204	66,059
Commitments and contingencies (Notes 2 and 9)
Stockholders' equity:
Preferred stock, no par value Authorized-100,000 shares Issued-None
Common stock, $0.66 2/3 par value Authorized-20,000,000 shares Issued and outstanding- 7,980,202 shares at March 31, 2013 and 8,942,793 shares at March 31, 2012	5,320	5,961
Capital in excess of par value	41,458	95,971
Accumulated other comprehensive income (loss), net	(4)	16
Retained earnings	157,471	156,858
Total stockholders' equity	204,245	258,806
Total liabilities and stockholders' equity	$ 281,449	$ 324,865