INCOME TAXES (Tables)

12 Months Ended

Dec. 31, 2016

INCOME TAXES

Schedule of significant components of the Company's deferred tax assets

	As of December 31,
(In thousands)	2016			2015
Deferred tax assets
Net operating loss carryforwards	$	417,000		$	392,000
Deferred revenues		1,000			1,000
Research and development tax credit carryforwards		53,000			53,000
Other		13,000			17,000
Total deferred tax assets		484,000			463,000
Valuation allowance		(484,000	)		(463,000	)
Net deferred tax assets	$	—		$	—

Schedule of the differences between the U.S. federal statutory income tax rate to the Company's effective tax rate

	As of December 31,
	2016			2015			2014
U.S. federal income tax rate		35.00	%		34.00	%		35.00	%
Non-deductible executive compensation		1.55			(1.94	)		(0.16	)
Stock-based compensation		0.09			(0.23	)		(1.11	)
Federal and state research credits		—			—			12.66
Effect of Spin-Off Transaction		—			—			(203.20	)
Other		(0.29	)		(0.56	)		(4.04	)
Change in valuation allowance		(36.19	)		(31.27	)		160.85
Effective tax rate		0.16	%		—	%		—	%

Reconciliation of gross unrecognized tax benefits

A reconciliation of the beginning and ending balances of the total amounts of unrecognized tax benefits are as follows (in thousands):

Unrecognized tax benefits as of December 31, 2013	$	57,420
Gross decrease for tax positions for prior years		(42,650	)
Gross increase in tax portions for 2014		689
Unrecognized tax benefits as of December 31, 2014		15,459
Gross increase in tax portions for 2015		29
Unrecognized tax benefits as of December 31, 2016 and 2015	$	15,488