STOCKHOLDERS' EQUITY (Details 5)	12 Months Ended
	Dec. 31, 2013 item	Dec. 31, 2012
STOCKHOLDERS' EQUITY
Shares that were available for issuance	16,207,250	13,557,771
Purchase Plan
STOCKHOLDERS' EQUITY
Shares of common stock reserved for issuance	1,200,000
Shares issued under plan	936,596	843,610
Shares that were available for issuance	263,404
Maximum percentage of annual salary that can be withheld	10.00%
Maximum duration of offering period	12 months
Number of offering periods in which an employee can participate at a time	1
Number of consecutive purchase periods in an offering period	2
Duration of the purchase period	6 months
Percentage applied to common stock market value in calculating purchase price under purchase plan	85.00%
Duration of the new offering period	12 months
Period for which shares must be held after purchase under the Purchase Plan before being eligible to be traded	1 year