CAPITAL STRUCTURE, COMMON STOCK (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Dec. 31, 2014	Jul. 03, 2013	Apr. 30, 2012
Class of Stock [Line Items]
Preferred stock, shares authorized (in shares)	15,000,000		15,000,000
Preferred stock, par value (in dollars per share)	$ 0.001		$ 0.001
Common stock, shares authorized (in shares)	150,000,000		150,000,000
Common stock, par value (in dollars per share)	$ 0.001		$ 0.001
Common stock, voting rights	One vote for each share held
Common stock issued (in shares)	69,394,765		68,861,366
Common stock outstanding (in shares)	69,394,765		68,861,366
Class of Warrant or Right [Line Items]
Price per share (in dollars per share)	$ 4.54	[1]
Series A Participating Preferred Stock [Member]
Class of Warrant or Right [Line Items]
Rights per share of common stock (in shares)	0.001
Price per share (in dollars per share)	$ 15
Maximum percentage of common stock held for rights become non-exercisable (in hundredths)	15.00%
Common share voting power of right (in shares)	0.007352
Common share payment of rights (in shares)	0.007352
Shares Issued under ATM Sales Agreement [Member]
Class of Stock [Line Items]
Common stock issued (in shares)	0
Maximum amount of common stock under ATM sales agreement				$ 100.0	$ 40.0
Sales commission percentage for sales made under ATM (in hundredths)	3.00%

[1] Weighted-average exercise price