QUARTERLY SUPPLEMENTAL FINANCIAL DATA (UNAUDITED) (Details) (USD $)	3 Months Ended									12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 49,478,000	[1]	$ 32,826,000	$ 49,359,000	$ 14,976,000	$ 28,133,000	$ 12,504,000	$ 29,987,000	$ 12,620,000	$ 146,639,000	$ 83,244,000	$ 61,289,000
Net (loss) income	57,886,000		5,542,000	15,382,000	(4,758,000)	5,385,000	(5,468,000)	10,964,000	(1,221,000)	74,052,000	9,660,000	3,155,000
Net income loss per common share [Abstract]
Basic (in dollars per share)	$ 1.26		$ 0.12	$ 0.34	$ (0.10)	$ 0.12	$ (0.12)	$ 0.24	$ (0.03)	$ 1.61	$ 0.21	$ 0.07
Diluted (in dollars per share)	$ 1.24		$ 0.12	$ 0.33	$ (0.10)	$ 0.12	$ (0.12)	$ 0.23	$ (0.03)	$ 1.59	$ 0.21	$ 0.07
Revenue recognized relating to cash payments received	1,500,000					1,900,000				1,500,000	1,900,000
Reversal of accrued bonus compensation						$ 703,000

[1] ncludes $1.5 million of revenue that was recognized relating to cash payments received in a prior year that were creditable against license fees and/or royalties for which the Company determined there was no appreciable likelihood of executing a commercial license agreement with the customer (see Note 2).