Note K - Business Segments and Foreign Operations - Net Sales by Product Group (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Net Sales	$ 246,838	$ 302,663
Operating Segments [Member]
Net Sales	323,389	386,909
Intersegment Eliminations [Member]
Net Sales	(76,551)	(84,246)
Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	227,565	280,428
Distribution Segment [Member] | Operating Segments [Member]
Net Sales	95,824	106,481
Industrial [Member]
Net Sales	26,343	34,042
Industrial [Member] | Intersegment Eliminations [Member]
Net Sales	(3,434)	(4,430)
Industrial [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	24,143	30,393
Industrial [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	5,634	8,079
Land Based Transmissions [Member]
Net Sales	62,697	112,793
Land Based Transmissions [Member] | Intersegment Eliminations [Member]
Net Sales	(26,525)	(28,950)
Land Based Transmissions [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	63,523	111,260
Land Based Transmissions [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	25,699	30,483
Marine and Propulsion Systems [Member]
Net Sales	152,501	150,237
Marine and Propulsion Systems [Member] | Intersegment Eliminations [Member]
Net Sales	(46,544)	(50,796)
Marine and Propulsion Systems [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	139,833	138,704
Marine and Propulsion Systems [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	59,212	62,329
Other [Member]
Net Sales	5,297	5,591
Other [Member] | Intersegment Eliminations [Member]
Net Sales	(48)	(70)
Other [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	66	71
Other [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	$ 5,279	$ 5,590