Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

The components of the Company’s deferred tax assets and liabilities, all of which are long-term, are as follows (in thousands):

	December 31,
	2015			2014
Deferred tax assets:
Net operating loss carryforwards	$	105,661		$	86,541
Tax credit carryforwards		27,671			22,716
Equipment, furnishings and other		10,547			14,396
Total deferred tax assets		143,879			123,653
Deferred tax liabilities		(270	)		(187	)
Net deferred tax assets		143,609			123,466
Valuation allowance		(143,609	)		(123,466	)
	$	—		$	—

Effective Income Tax Rate Reconciliation

The provision for income taxes differs from the provision computed by applying the Federal statutory rate to net loss before income taxes as follows (in thousands):

	Years ended December 31,
	2015			2014			2013
Federal benefit at statutory rate	$	(19,919	)	$	(10,240	)	$	(16,145	)
State income taxes, net of Federal taxes		(3,556	)		(2,773	)		(1,517	)
State credits		(1,324	)		(990	)		(787	)
Warrant liabilities		(1,509	)		(6,477	)		6,871
Other permanent differences		16			37			14
Provision related to change in valuation allowance		20,142			23,440			14,606
Current year tax credit		(2,050	)		(1,300	)		(1,034	)
Return to provision		8,198			(1,504	)		(2,011	)
Other, net		3			(192	)		5
	$	1		$	1		$	2