Income Taxes - Temporary Differences (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Accrued expenses and other reserves	$ 1,550	$ 1,787
Right-of-use-asset	(73)	(225)
Lease liabilities	88	271
Tax credits, deferred R&D, and other	49	20
Net operating loss	17,318	14,510
Valuation allowance	(18,932)	(16,363)
Net deferred tax assets	$ 0	$ 0

Deferred Tax Assets, Leasing Arrangements

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from in-process research and development costs expensed in connection with a business combination.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 6
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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from reserves and accruals, classified as other.

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Paragraph 2
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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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- References

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