Income Taxes (Tables)

12 Months Ended

Dec. 31, 2021

Income Tax Disclosure [Abstract]

Schedule of Reconciliation of Federal Statutory Rate on Loss before Income Taxes and before Gain from Sale of Equity Method Investment Rate to Effective Income Tax Rate

The reconciliation of the federal statutory rate on the income before income taxes to the effective income tax rate for the years ended December 31 is as follows:

	2021			2020			2019
Statutory federal tax rate		21.0	%		21.0	%		21.0	%
State income taxes, net of federal income tax benefit		(4.2	)		(0.5	)		(8.1	)
Increase in valuation allowance		9.2			41.2			2.2
Permanent items		(17.9	)		(48.7	)		(3.9	)
Tax credits		(5.7	)		(11.2	)		(15.6	)
Provision vs. tax return differences		(2.0	)		0.7			9.0
Foreign rate differential and deferred items		—			0.1			0.6
Other		(0.1	)		0.3			—
		0.3	%		2.9	%		5.2	%

Schedule of Domestic and Foreign Components of Income (Loss) Before Income Taxes and before the Gain from Sale of Equity Method Investment

For financial reporting purposes, income before income taxes for the years ended December 31 include the following components (in thousands):     

	2021		2020		2019
Domestic	$	56,620	$	17,688	$	13,493
Foreign		185		773		1,394
	$	56,805	$	18,461	$	14,887

Schedule of Components of Provision (Benefit) for Income Taxes

Significant components of the provision (benefit) for income taxes for the years ended December 31 are as follows (in thousands):

	2021			2020			2019
Current:
Federal	$	1		$	215		$	—
State		(14	)		93			268
Foreign		171			252			450
		158			560			718
Deferred:
Foreign		18			(21	)		60
		18			(21	)		60
	$	176		$	539		$	778

Schedule of Significant Components of Deferred Tax Assets and Liabilities

Significant components of the Company’s deferred tax assets and liabilities as of December 31 were as follows (in thousands):

	2021			2020
Deferred tax assets:
Research and development tax credit carryforwards	$	36,041		$	29,046
Net operating loss carryforwards		5,985			5,923
Stock-based compensation		2,341			1,796
Inventory reserves		2,268			2,282
Investment tax credit carryforwards		1,928			1,927
UNICAP		1,363			1,336
Vacation accrual		1,338			1,349
Lease liabilities		787			518
Accrued payroll tax deferral		384			764
Other		1,568			1,197
Total deferred tax assets		54,003			46,138
Less: Valuation allowance for deferred tax assets		(43,329	)		(37,856	)
Net deferred tax assets		10,674			8,282
Deferred tax liabilities:
Depreciation		(9,048	)		(6,809	)
ROU assets		(756	)		(490	)
Prepaid expenses		(662	)		(616	)
Other		—			(141	)
Total deferred tax liabilities		(10,466	)		(8,056	)
Net deferred tax assets (liabilities)	$	208		$	226

Schedule of 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):

	2021			2020			2019
Balance on January 1	$	2,297		$	2,070		$	1,462
Additions based on tax positions related to the current year		625			244			571
Additions (reductions) for tax positions of prior years		393			(13	)		43
Lapse of statute		(69	)		(4	)		(6	)
Balance on December 31	$	3,246		$	2,297		$	2,070