Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Additional Information (Detail)

v3.20.1
Fair Value Measurements - Additional Information (Detail)
Apr. 30, 2020
USD ($)
Fair Value Measurements Disclosure [Line Items]  
Marketable securities fair value, mature between one and two years $ 257,000
Fair Value, Inputs, Level 3 [Member]  
Fair Value Measurements Disclosure [Line Items]  
Fair value measurements of our financial assets $ 0