Annual report pursuant to Section 13 and 15(d)

Income Taxes - Schedule of Tax Effects of Temporary Differences and Related Deferred Tax Assets and Liabilities (Details)

v3.20.4
Income Taxes - Schedule of Tax Effects of Temporary Differences and Related Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Deferred tax assets:    
Depreciation and other $ 235 $ 263
Net operating loss carryforwards 43,241 40,683
Research and development tax credits 1,837 1,817
Accruals and reserves 380 289
Deferred revenue 401 220
Stock compensation expense 2,547 2,197
Lease assets 110 224
Other 37 45
Deferred tax liabilities:    
Lease liabilities (88) (214)
Prepaid expenses (27) (43)
Less: Valuation allowance (48,673) (45,481)
Net deferred tax asset (liability) $ 0 $ 0