Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

Income Taxes

Schedule of components of deferred tax assets

	2019		2018
	(In thousands)
Operating loss carryforwards	$	81,403	$	70,509
Tax credit carryforwards		23,072		18,514
Lease liabilities		308		—
Other		7,994		8,627
Total deferred tax assets		112,777		97,650
Right-of-use asset		(306)		—
Valuation allowance		(112,471)		(97,650)
Net deferred tax assets	$	—	$	—

Schedule of difference between U.S. federal corporate tax rate and Company effective tax rate

	2019		2018		2017
Expected federal income tax rate	(21.0)	%	(21.0)	%	(34.0)	%
Expiring credits and NOLs	—		1.0		—
Change in valuation allowance	26.2		37.9		0.9
Federal and state credits	(8.1)		(7.4)		(6.9)
State income taxes, net of federal benefit	(4.7)		(9.7)		(3.7)
Permanent differences	4.8		0.5		2.4
Rate change related to TCJA	—		—		41.9
Other	2.8		(1.3)		(0.6)
Effective tax rate	0.0	%	0.0	%	0.0	%