XML 73 R62.htm IDEA: XBRL DOCUMENT v3.20.4
Fair Value Measurements (Details Narrative) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Jan. 31, 2021
Jan. 31, 2020
Jan. 31, 2021
Jan. 31, 2020
Fair Value Disclosures [Abstract]        
Gain due to the change in fair value of warrant liabilities $ 6