Segment Information (Details) - Reconciliation of Revenue from Segments to Consolidated - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2021	Apr. 30, 2020
Revenues:
Revenues	$ 54,254	$ 41,507
Frequency Electronics Inc New York [Member]
Revenues:
Revenues	42,400	31,751
Frequency Electronics Inc Zyfer [Member]
Revenues:
Revenues	13,835	10,914
Inter Segment [Member]
Revenues:
Revenues	$ (1,981)	$ (1,158)