Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Additional Information (Details)

v3.19.2
Stock-based Compensation - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended 12 Months Ended
May 13, 2019
Apr. 10, 2019
Sep. 10, 2018
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Number of shares exercised           72,034    
Compensation expense       $ 5,557 $ 33 $ 5,604 $ 66  
Accelerated vesting of options           1,115,256    
Unamortized stock-based compensation cost related to unvested stock options       2,700   $ 2,700    
Unamortized stock-based compensation cost, weighted average period of recognition           3 years    
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       17,314 1,520 72,034 9,977  
Restricted stock award, fully vested shares       220,758        
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              
Restricted Stock Unit                
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Aggregate restricted stock units, granted   128,000            
Restricted Stock Award                
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Compensation expense       $ 4,215        
2012 Equity Incentive Plan                
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Number of shares available to be issued       0   0    
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       1,885,039   1,885,039    
2019 Employee Stock Purchase Plan                
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Common stock, number of shares available for sale       337,007   337,007    
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%   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   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.    
Number of shares issued           0    
2019 Plan                
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]                
Common stock, number of shares available for sale       1,885,039   1,885,039    
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%   5.00%    
Common stock reserved for issuance description           1,885,039 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.