NOTE J - RECENTLY ISSUED ACCOUNTING PRONOUNCEMENTS (Details) - Disaggregation of Revenue - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Oct. 31, 2018	Oct. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 12,142	$ 9,337	$ 23,153	$ 21,360
Topic 606 (POC) Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	11,148		20,396
POT Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	994		2,757
Frequency Electronics Inc New York [Member]
Disaggregation of Revenue [Line Items]
Revenue	9,745	6,579	18,322	15,740
Frequency Electronics Inc New York [Member] | Topic 606 (POC) Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	9,120		17,199
Frequency Electronics Inc New York [Member] | POT Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	625		1,123
Frequency Electronics Inc Zyfer [Member]
Disaggregation of Revenue [Line Items]
Revenue	2,542	3,593	5,103	7,865
Frequency Electronics Inc Zyfer [Member] | Topic 606 (POC) Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	2,058		3,233
Frequency Electronics Inc Zyfer [Member] | POT Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	484		1,870
Inter Segment [Member]
Disaggregation of Revenue [Line Items]
Revenue	(145)	$ (835)	(272)	$ (2,245)
Inter Segment [Member] | Topic 606 (POC) Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	(30)		(36)
Inter Segment [Member] | POT Revenue [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ (115)		$ (236)