Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Tax Disclosure [Abstract]

Deferred Tax Assets

Deferred tax assets consist of the following:

	December 31,
	2015			2014
Net operating tax loss and capital loss carryforwards	$	65,783		$	60,380
Capitalized research and development costs	2,890			—
Research and development tax credits	950			534
Deferred compensation	106			168
Other accruals and reserves	1,092			670
Basis of intangible assets	4,197			4,610
Total deferred tax asset	75,018			66,362
Less valuation allowance	(75,018		)	(66,362		)
Net deferred tax asset	$	—		$	—

Reconciliation of Unrecognized Tax Benefits

A reconciliation of the Company’s unrecognized tax benefits from January 1, 2015 through December 31, 2015 is provided in the following table (in thousands):

	Year Ended December 31,
	2015		2014
Beginning balance	$	2,822	$	2,795
Change in current period positions	56		34
Change in prior period positions	4		(7		)
Ending balance	$	2,882	$	2,822

Reconciliation of Income Taxes

The reconciliation of income taxes computed using the statutory United States income tax rate and the provision (benefit) for income taxes for continuing operations for the years ended December 31, 2015, 2014, and 2013, are as follows:

	Year Ended December 31,
	2015		2014		2013
Federal statutory tax rate	(34	)%	(34	)%	(34	)%
State taxes, net of federal benefit	—	%	(1	)%	(1	)%
Valuation allowance	45	%	22	%	37	%
Prior year true-ups	(1	)%	17	%	1	%
Revaluation of warrants	(6	)%	—	%	—	%
Permanent differences	(2	)%	(3	)%	(1	)%
Tax credits	(2	)%	(1	)%	(2	)%
Income tax expense	—	%	—	%	—	%