STOCK-BASED COMPENSATION (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Stock-based compensation
Compensation expense	$ 8,930	$ 6,108	$ 5,070
Inventory
Stock-based compensation
Compensation expense	0	0	0
Cost of sales
Stock-based compensation
Compensation expense	14	42	41
Research and development expense.
Stock-based compensation
Compensation expense	258	364	568
Selling general and administrative expense
Stock-based compensation
Compensation expense	$ 8,658	$ 5,702	$ 4,461