Provision for Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Tax Disclosure [Abstract]

Schedule of Provision for Income Taxes Differs from Amount Expected by Applying Federal Statutory Rate to Loss Before Taxes

The provision for income taxes differs from the amount expected by applying the federal statutory rate to the loss before taxes as follows:

	Year Ended December 31, 2018			Year Ended December 31, 2017			Year Ended December 31, 2016
Federal statutory income tax rate		21.00	%		34.00	%		34.00	%
Non-deductible expenses and other		(1.54	)%		(1.23	)%		(0.22	)%
Change in valuation allowance		(19.46	)%		(16.46	)%		(33.78	)%
Remeasurement of federal tax rate change		—			(16.32	)%		—
Total		0.00	%		0.00	%		0.00	%

Schedule of Components of Deferred Tax Assets

As of December 31, 2018 and 2017, the components of the Company’s deferred tax assets are as follows (in thousands):

	Year Ended December 31, 2018			Year Ended December 31, 2017
Deferred tax assets:
Federal and state net operating loss carryforwards	$	16,076		$	11,101
Research and development credits carryforwards		5,087			2,706
Depreciation		3,942			3,489
Deferred Revenue		3,909			—
Other		1,724			1,292
Total deferred tax assets		30,738			18,588
Less valuation allowance		(30,738	)		(18,588	)
Net deferred tax assets	$	—		$	—

Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands):

	Year Ended December 31, 2018		Year Ended December 31, 2017		Year Ended December 31, 2016
Beginning balance	$	622	$	242	$	19
Additions for tax positions taken in a prior year		8		29		—
Additions for tax positions taken in current year		454		351		223
Ending balance	$	1,084	$	622	$	242