STOCK-BASED COMPENSATION - Stock-based Compensation (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 1,433,000	$ 1,565,000	$ 2,304,000
Cost of Sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	52,000	68,000	82,000
Research, Development and Engineering
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	254,000	308,000	367,000
Selling, General and Administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	1,127,000	1,189,000	1,855,000
Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	1,289,000	1,527,000	2,167,000
Unrecognized stock-based compensation	1,500,000
Weighted average recognition period for stock-based compensation	1 year 9 months 21 days
Restricted Stock Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	124,000	18,000	112,000
Unrecognized stock-based compensation	400,000
Weighted average recognition period for stock-based compensation	3 years 1 month 23 days
Employee Stock Purchase Plan
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation	$ 20,000	$ 20,000	$ 25,000