WARRANTY RESERVES (Details) (USD $)	3 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012 Instruments [Member]	Jun. 30, 2012 Reagent Discs [Member]	Mar. 31, 2012 Reagent Discs [Member]
Product Warranty Liability [Line Items]
Period of coverage for standard warranty obligation on instruments, minimum (in years)			1 year
Period of coverage for standard warranty obligation on instruments, maximum (in years)			3 years
Change in accrued warranty reserve [Roll Forward]
Balance at beginning of period	$ 1,846,000	$ 1,222,000
Provision for warranty expense	307,000	343,000
Warranty costs incurred	(369,000)	(352,000)
Adjustment to pre-existing warranties	(290,000)	257,000
Balance at end of period	1,494,000	1,470,000
Non-current portion of warranty reserve	482,000	275,000
Current portion of warranty reserve	$ 1,012,000	$ 1,195,000		$ 562,000	$ 564,000