NET INCOME (LOSS) PER COMMON SHARE, SCHEDULE OF POTENTIALLY ANTIDILUTIVE SECURITIES (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	25,350	23,232	22,376	26,047
Employee stock options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	3,471	3,283	2,038	4,452
Employee stock purchase plan [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	218	174	218	88
Restricted stock and restricted stock units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	3,804	1,918	2,263	3,650
Convertible notes [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities	17,857	17,857	17,857	17,857