SUBSEQUENT EVENTS (Details) (Subsequent Events [Member], USD $)	0 Months Ended
	Jul. 23, 2013	Jul. 03, 2013
Subsequent Events [Member]
Subsequent Event [Line Items]
Maximum gross sales proceeds that may be raised pursuant to ATM offering		$ 100,000,000
Total amount of common stock sold pursuant to original Sales Agreement		38,300,000
Aggregate amount remaining available for future sales of common stock under ATM sales agreement		$ 56,500,000
Increase in share reserve available for issuance (in shares)	3,000,000
Aggregate share reserve available for issuance (in shares)	11,900,000
Ratio of restricted stock and restricted stock unit awards to stock option under fungible share counting provision	1.35