WARRANTY RESERVES (Details) (USD $)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Change in accrued warranty reserve [Roll Forward]
Balance at beginning of period	$ 1,846,000	$ 1,222,000	$ 1,343,000
Provision for warranty expense	1,228,000	1,698,000	1,294,000
Warranty costs incurred	(1,400,000)	(1,331,000)	(1,094,000)
Adjustment to pre-existing warranties	(290,000)	257,000	(321,000)
Balance at end of period	1,384,000	1,846,000	1,222,000
Non-current portion of warranty reserve	389,000	601,000	191,000
Current portion of warranty reserve	995,000	1,245,000	1,031,000
Instruments [Member]
Product Warranty Liability [Line Items]
Period of coverage for standard warranty obligation on instruments (in years)	one to three
Reagent Discs [Member]
Change in accrued warranty reserve [Roll Forward]
Provision for warranty expense	369,000	456,000	476,000
Warranty reserve, balance at end of period	571,000	564,000
Current portion of warranty reserve	$ 571,000	$ 564,000