NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 3) (USD $)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Revenue Recognition
Unbilled costs and fees expected to be billed and collected during fiscal 2013	$ 4,839,000
Percentage of unbilled costs and fees expected to be billed and collected during fiscal 2013	99.00%
Retainages	80,000	87,000
Commercial contract retentions and government contract withholdings as a percent of fees	15.00%
Warranty Costs
Parts and labor warranty period for certain of the company's products with purchase of domestic equipment	1 year
Warranty period for certain products	1 year
Deferred Revenue
Minimum period covered under extended warranty and service contracts	1 year
Maximum period covered under extended warranty and service contracts	5 years
Impairment of Long-Lived Assets
Impairment costs	0	0	0
Accrued Salaries and Benefits
Accrued payroll and payroll related taxes	1,995,000	2,140,000
Accrued incentive compensation	4,633,000	7,486,000
Accrued vacation	1,739,000	2,096,000
Accrued severance	1,607,000
Total accrued salaries and benefits	9,974,000	11,722,000
Other Current Liabilities
Accrued accounts payable and other expenses	4,213,000	999,000
Accrued contract related costs	7,596,000	2,808,000
Accrued audit and legal fees	375,000	523,000
Accrued sales commissions	2,010,000	1,659,000
Total other current liabilities	14,194,000	5,989,000
Research and Development
Research and development costs	23,618,000	25,544,000	22,619,000
Revenue recognized related to government-sponsored research and development	2,124,000	4,409,000	4,821,000
Common stock equivalents excluded from diluted earnings per share as their effect is anti-dilutive (in shares)	182,000	64,000	35,000
Earnings Per Share - Basic:
Net income	17,454,000	21,422,000	42,817,000
Weighted average number of common shares outstanding - basic	8,394,000	9,046,000	9,045,000
Income per share - basic (in dollars per share)	$ 2.08	$ 2.37	$ 4.73
Earnings Per Share - Diluted:
Net income	$ 17,454,000	$ 21,422,000	$ 42,817,000
Weighted average number of common shares outstanding - basic	8,394,000	9,046,000	9,045,000
Assumed exercise of stock options, warrants, restricted stock and restricted stock units, using the treasury stock method (in shares)	54,000	102,000	202,000
Weighted average number of common and potential common shares outstanding - diluted	8,448,000	9,148,000	9,247,000
Income per share - diluted (in dollars per share)	$ 2.07	$ 2.34	$ 4.63
Minimum
Revenue Recognition
Period of certain long-term, custom-built systems or contract engineering projects	1 year
Maximum
Revenue Recognition
Period of certain long-term, custom-built systems or contract engineering projects	4 years
Parts only or parts and labor warranty period for certain of the products with purchase of international equipment	1 year