XML 101 R83.htm IDEA: XBRL DOCUMENT v3.20.4
Income Taxes - Reconciliation of Income Taxes Computed at Federal Statutory Rate and Provision for Income Taxes (Detail)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Income Tax Disclosure [Abstract]      
Federal statutory rate 21.00% 21.00% 21.00%
State taxes, net of federal benefit (0.10%) (0.20%) (0.20%)
Permanent differences (4.00%) (2.80%) 0.20%
Stock-based compensation 12.10% 22.30% 9.30%
Federal research and development credit 1.10% 1.30% 1.20%
Foreign rate differential (1.40%) (1.40%) (1.10%)
Change in valuation allowance (30.00%) (41.00%) (32.80%)
Other (0.80%) 0.70% 1.50%
Effective income tax rate (2.10%) (0.10%) (0.90%)