Segment Information (Details) - Reconciliation of Revenue from Segments to Consolidated - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Net revenues:
Revenues	$ 41,507	$ 49,509
Frequency Electronics Inc New York [Member]
Net revenues:
Revenues	31,751	38,096
Frequency Electronics Inc Zyfer [Member]
Net revenues:
Revenues	10,914	12,235
Inter Segment [Member]
Net revenues:
Revenues	$ (1,158)	$ (822)