FAIR VALUE OF FINANCIAL INSTRUMENTS (Details 2) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reconciliation of the beginning and ending balances of the fair value measurements using significant unobservable inputs (Level 3)
Settlements made in cash	$ 80,500,000
Issuance of warrants to purchase common stock (in shares)	1,525,272
Warrant Liability
Reconciliation of the beginning and ending balances of the fair value measurements using significant unobservable inputs (Level 3)
Balance at the beginning of the period	127,764,000	227,348,000
Warrant liability loss (gain)	185,017,000	(101,584,000)	140,900,000
Settlements	(189,208,000)
Purchases		2,000,000	86,448,000
Balance at the end of the period	$ 123,573,000	$ 127,764,000	$ 227,348,000
Warrant Liability | Significant Unobservable Inputs (Level 3)
Reconciliation of the beginning and ending balances of the fair value measurements using significant unobservable inputs (Level 3)
Expected Volatility (as a percent)	29.00%