Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Income Taxes

Schedule of reconciliation of the U.S. statutory income tax rate to the Company's effective tax rate

	December 31,
	2015			2014			2013
Federal income tax (benefit) at statutory rate		(34.0	)%		(34.0	)%		(34.0	)%
Change in tax rate		0.3	%		2.1	%		0.0	%
Permanent items		1.3	%		1.0	%		4.9	%
Other		0.0	%		0.1	%		0.0	%
Change in valuation allowance		32.4	%		30.8	%		29.1	%
Effective income tax rate		0.0	%		0.0	%		0.0	%

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

	December 31,
	2015			2014
	(in thousands)
Deferred tax assets:
Federal and state operating loss carryforwards	$	45,848		$	33,099
Equity compensation		4,387			971
Temporary differences		341			138
Total deferred tax assets		50,576			34,208
Valuation allowance		(50,576	)		(34,208	)
Net deferred tax assets	$	—		$	—