XML 52 R43.htm IDEA: XBRL DOCUMENT v3.19.1
Stock Options and Share-Based Compensation - Additional Information (Detail) - 2017 Plan - Restricted Stock Units (RSUs) - USD ($)
1 Months Ended 3 Months Ended 9 Months Ended
Jun. 30, 2018
Jan. 31, 2019
Jan. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Restricted stock units granted 17,769    
Vesting period     3 years
Stock-based compensation expense   $ 45,000 $ 106,000
Remaining estimated compensation expense   $ 406,000 $ 406,000