Note H - Segment Information (Details Textual) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Number of Reportable Segments	2
Revenue from Contract with Customer, Including Assessed Tax	$ 29,195	$ 36,532
Non-US [Member]
Revenue from Contract with Customer, Including Assessed Tax	11,010	18,886
UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 18,185	$ 17,646
Products Manufactured by NAIE [Member] \| Non-US [Member] \| Revenue Benchmark [Member] \| Product Concentration Risk [Member]
Concentration Risk, Percentage	89.00%	72.00%
Products Manufactured by NAIE [Member] \| UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6351-108592

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13531-108611

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Section 50
-Paragraph 21
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-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13537-108611

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=99393423&loc=d3e6404-108592

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