Annual report pursuant to Section 13 and 15(d)

Stock-based Compensation - Additional Information (Details)

v3.20.1
Stock-based Compensation - Additional Information (Details) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
May 13, 2019
Apr. 10, 2019
Sep. 10, 2018
Dec. 31, 2019
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares exercised       95,739 15,475
Tax obligations recorded as reduction in additional paid in capital       $ (1,897)  
Compensation expense       $ 6,308 $ 252
Accelerated vesting of options       1,058,169  
Unamortized stock-based compensation cost related to unvested stock options       $ 4,019  
Unamortized stock-based compensation cost, weighted average period of recognition       3 years  
Pre-tax intrinsic value of options exercised       $ 266 $ 94
Weighted average options grant fair value       $ 2.84 $ 1.85
Expected dividend yield       0.00% 0.00%
IPO          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Compensation expense       $ 287  
Chief Financial Officer | IPO          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Accelerated vesting of options     201,666    
Common Stock          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares exercised       95,739 15,475
Common Stock | Chief Executive Officer          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Restricted stock award, fully vested shares 383,197        
Restricted stock award, net shares issued 210,758        
Restricted stock award, shares withheld to satisfy tax obligations 172,439        
Tax obligations recorded as reduction in additional paid in capital $ 1,897        
Restricted Stock Unit          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Aggregate restricted stock units, granted   128,000     287,500
Aggregate restricted stock units, outstanding       90,000 249,500
Aggregate restricted stock units, forfeited       38,000 38,000
Restricted Stock Award          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Aggregate restricted stock units, outstanding       249,500  
Compensation expense       $ 4,215  
Stock issued during period         0
2012 Equity Incentive Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares available to be issued       944,828 455,557
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 Equity Incentive Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of shares available to be issued       0  
2019 Employee Stock Purchase Plan          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
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  
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%  
Number of shares issued       68,606  
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.