Note H - Segment Information (Details Textual) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2022 USD ($)	Mar. 31, 2021 USD ($)
Number of Reportable Segments	2
Revenue from Contract with Customer, Including Assessed Tax	$ 42,373	$ 46,320	$ 118,440	$ 134,129
Non-US [Member]
Revenue from Contract with Customer, Including Assessed Tax	12,991	18,646	40,161	63,595
UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	29,382	27,674	78,279	70,534
Products Manufactured by NAIE [Member] | UNITED STATES
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 0
Products Manufactured by NAIE [Member] | Revenue Benchmark [Member] | Product Concentration Risk [Member] | Non-US [Member]
Concentration Risk, Percentage	85.00%	65.00%	84.00%	79.00%