XML 67 R51.htm IDEA: XBRL DOCUMENT v3.20.2
Inventories (Details) - USD ($)
$ in Millions
Apr. 30, 2020
Apr. 30, 2019
Frequency Electronics Inc Zyfer [Member]    
Inventories (Details) [Line Items]    
Inventory Adjustments $ 5.0 $ 1.1
Frequency Electronics Inc New York [Member]    
Inventories (Details) [Line Items]    
Inventory, Work in Process, Net of Reserves $ 6.6