SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Net Loss Per Common Share (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
Numerator:
Net 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
Denominator:
Weighted average common shares outstanding - Basic (in shares)									45,898,019	45,951,276	43,737,968
Effect of dilutive shares:
Common stock equivalents arising from stock options and ESPP (in shares)									458,574	648,661	956,803
Restricted stock awards and units (in shares)									187,012	283,665	445,623
Weighted average common shares outstanding - Diluted (in shares)									46,543,605	46,883,602	45,140,394
Net income (loss) per common share:
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
Anti-dilutive shares excluded from the calculation of diluted net loss per common share (in shares)									140,839	212,941	586,972
Deferred revenue [Abstract]
Deferred revenue under license agreements not yet executed or deemed effective	4,300,000				0				4,300,000	0
Deferred revenue, revenue recognized	1,500,000				1,900,000				1,500,000	1,900,000
License fee agreement, term of agreement (in years)									6 years 4 months 24 days
Accounts receivable [Abstract]
Unbilled receivables, current	92,000				308,000				92,000	308,000
Research and Development [Abstract]
Development and operations in the Company’s facilities									23,491,000	21,381,000	18,707,000
Costs incurred under sponsored research agreements									2,671,000	2,058,000	1,022,000
PPG OLED Materials Agreement (Note 7)									7,470,000	6,170,000	3,539,000
Scientific Advisory Board compensation									583,000	423,000	861,000
Research and Development Expense, Total									$ 34,215,000	$ 30,032,000	$ 24,129,000