Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Additional Information (Details)

v3.20.1
Stock-based Compensation - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of shares exercised 240,125    
Unamortized stock-based compensation cost related to unvested stock options $ 2,901    
Unamortized stock-based compensation cost, weighted average period of recognition 3 years    
Restricted Stock      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of shares, Unvested 226,500    
Stock issued during period 0 0  
2019 Equity Incentive Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of shares available to be issued 2,174,999    
Increase In common stock reserved for issuance of number of shares of capital stock outstanding 1,021,861    
2019 Employee Stock Purchase Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Number of shares available to be issued 472,773    
Common stock, number of shares available for sale 541,379    
Period in which reserved shares will increase annually 10 years    
Increase in common stock reserved for issuance as a percentage of total number of shares of capital stock outstanding on the last day of the prior calendar year 1.00%    
Increase In common stock reserved for issuance of number of shares of capital stock outstanding on last day of prior calendar year 500,000    
Increase In common stock reserved for issuance of number of shares of capital stock outstanding 204,372    
Common stock reserved for issuance description Additionally, the number of shares of common stock reserved for issuance under the 2019 Employee Stock Purchase Plan will automatically increase on January 1 of each calendar year for 10 years, starting January 1, 2020, and ending on, and including, January 1, 2029, in an amount equal to the lesser of 1% of the total number of shares of capital stock outstanding on December 31st of the prior calendar year, and (ii) 500,000 shares, unless the board of directors or compensation committee determines prior to such date that there will be a lesser increase, or no increase.    
Percentage of shares purchased at fair market value of common stock 85.00%    
2012 Equity Incentive Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Expiration period 10 years    
Number of shares exercised 0   0
2012 Equity Incentive Plan | Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Vesting period 2 years    
2012 Equity Incentive Plan | Maximum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Vesting period 4 years    
2012 Equity Incentive Plan | Options and SARs | Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Exercise price options granted from fair value common stock, percent 100.00%    
2012 Equity Incentive Plan | Granted to Ten Percent Stockholders | Minimum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Exercise price options granted from fair value common stock, percent 110.00%    
2012 Equity Incentive Plan | Granted to Ten Percent Stockholders | Maximum      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Vesting period 5 years    
2019 Plan      
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]      
Common stock, number of shares available for sale 2,906,900    
Period in which reserved shares will increase annually 10 years    
Increase in common stock reserved for issuance as a percentage of total number of shares of capital stock outstanding on the last day of the prior calendar year 5.00%    
Common stock reserved for issuance description 2,906,900 shares of common stock are reserved for future issuance under the 2019 Equity Incentive Plan, plus the number of shares subject to outstanding stock options or other stock awards that were granted under the 2012 Option Plan that are forfeited, terminated, expire or are otherwise not issued. Additionally, the number of shares of common stock reserved for issuance under the 2019 Equity Incentive Plan will automatically increase on January 1 of each calendar year for 10 years, starting January 1, 2020 and ending on and including January 1, 2029, in an amount equal to 5% of the total number of shares of capital stock outstanding on December 31 of the prior calendar year, unless the board of directors or compensation committee determines prior to the date of increase that there will be a lesser increase, or no increase.