STOCK-BASED COMPENSATION - Stock-based Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 1,565,000	$ 2,304,000	$ 2,744,000
Cost of Sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	68,000	82,000	96,000
Research, Development and Engineering
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	308,000	367,000	451,000
Selling, General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	1,189,000	1,855,000	2,197,000
Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	1,527,000	2,167,000	2,442,000
Unrecognized stock-based compensation	2,900,000
Weighted average recognition period for stock-based compensation	1 year 11 months 1 day
Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	18,000	112,000	263,000
Unrecognized stock-based compensation	21,000
Weighted average recognition period for stock-based compensation	3 years 3 months 15 days
Employee Stock Purchase Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 20,000	$ 25,000	$ 39,000