Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Income Tax Disclosure [Abstract]

Effective Income Tax Rate Reconciliation

The difference between income taxes expected at the U.S. federal statutory income tax rate of 21% and the reported income tax expense (benefit) are summarized as follows:

	Year Ended December 31,
	2020			2019
Income tax at statutory rate	$	(4,661)		$	(2,703)
Valuation allowance	4,408			2,948
State income tax, net of federal benefit	(330)			(606)
Business tax credit net of reserves	—			—
Non-deductible expenses	585			365
Foreign income taxes at different rate	—			1
Income tax expense	$	2		$	5
Effective tax rate	(0.01)		%	(0.04)		%

Provision Expense for Income Taxes

The provision expense for income taxes consists of the following:

	Year Ended December 31,
	2020		2019
Current:
Federal	$	—	$	—
State	2		5
Foreign	—		—
Total current	2		5
Deferred:
Federal	—		—
State	—		—
Foreign	—		—
Total deferred	—		—
Total	$	2	$	5

Components of Net Deferred Income Taxes

The components of net deferred income taxes consist of the following:

	December 31,
	2020		2019
Deferred tax assets:
Net operating loss	$	30,705	$	26,285
Reserves and accruals	3,739		3,842
Tax credits	1,193		1,463
Gross deferred tax assets	35,637		31,590
Less valuation allowance	(35,100)		(31,349)
Total deferred tax assets	537		241
Deferred tax liabilities:
Amortization of acquired intangibles	(537)		(241)
Total deferred tax liabilities	(537)		(241)
Net deferred tax liabilities	$	—	$	—

Reconciliation of Unrecognized Tax Benefits

The following is a tabular reconciliation of the total amounts of unrecognized tax benefits:

	December 31,
	2020		2019
Unrecognized tax benefits, beginning of period	$	1,531	$	1,516
Tax positions taken in prior periods:
Gross increases	69		—
Gross decreases	(297)		—
Tax positions taken in current period:
Gross increases	11		15
Settlements	—		—
Lapse of statute of limitations	—		—
Unrecognized tax benefits, end of period	$	1,314	$	1,531

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