EQUITY AND CASH COMPENSATION UNDER THE PPG AGREEMENTS - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Mar. 31, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Long-term Purchase Commitment [Line Items]
Percent Of Services Payable In Cash Or Shares	50.00%				50.00%
Issuance of common stock in connection with materials and license agreements (in shares)	0	0			0	0
New OLED Materials Agreement and OLED Materials Agreement [Member] | Cash Distribution
Long-term Purchase Commitment [Line Items]
Charges to expense for cash portion of reimbursement of expenses	$ 395	$ 2,700			$ 2,300	$ 5,700
New OLED Materials Agreement and OLED Materials Agreement [Member] | Weighted Average
Long-term Purchase Commitment [Line Items]
Minimum average closing price of common stock (in dollars per share)			$ 20.00	$ 20.00