Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income Taxes

Schedule of income (loss) before income taxes

	Year Ended
	December 31,
	2018		2017
U.S.	$	(21,378)	$	(30,168)
Foreign		(1,740)		284
Loss before income taxes	$	(23,118)	$	(29,884)

Schedule of Company's current and deferred expense for income tax

	Year Ended
	December 31,
	2018		2017
Current expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		—		—
Total current expense (benefit):	$	—	$	—
Deferred expense (benefit):
Federal	$	—	$	—
State		—		—
Foreign		20		(157)
Total deferred expense (benefit):	$	20	$	(157)
Total income tax expense (benefit):	$	20	$	(157)

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

	Year Ended
	December 31,
	2018		2017
Federal statutory income tax rate	21.00	%	34.00	%
State taxes, net of federal benefit	7.76	%	4.42	%
Permanent differences	2.38	%	(2.27)	%
Tax credits	6.94	%	3.45	%
Tax law change	0.00	%	(37.65)	%
Foreign rate differential	0.68	%	(0.02)	%
Valuation allowance	(38.26)	%	(3.11)	%
Other	(0.59)	%	1.68	%
	(0.09)	%	0.50	%

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

	Year Ended
	December 30,
	2018		2017
Federal net operating loss carryforwards	$	38,531	$	33,232
State net operating loss carryforwards		5,553		4,014
Stock Options		1,632		1,348
Federal research tax credits		2,811		1,799
State research tax credits		382		231
License fees		1,495		1,659
Accrued expenses		88		29
Other		149		182
Total deferred tax assets	$	50,641	$	42,494
Valuation allowance		(50,517)		(42,336)
Net deferred tax asset (liability)	$	124	$	158