14. Segment Information (Details) - Schedule of Reconciliation of Assets from Segment to Consolidated (Parentheticals) - CNY (¥) ¥ in Millions	Apr. 30, 2019	Apr. 30, 2018
Frequency Electronics Inc New York [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Identifiable assets in China	¥ 1.5	¥ 1.5

Amount of assets classified as other.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.9-03(10))
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
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-Subparagraph (SX 210.7-03(a)(10))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Balance Type:	debit
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