Note J - Business Segments and Foreign Operations - Net Sales by Product Group (Details) - USD ($) $ in Thousands	12 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Net Sales	$ 218,581	$ 246,838
Operating Segments [Member]
Net Sales	291,731	323,389
Intersegment Eliminations [Member]
Net Sales	(73,150)	(76,551)
Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	191,510	227,565
Distribution Segment [Member] | Operating Segments [Member]
Net Sales	100,221	95,824
Industrial [Member]
Net Sales	23,454	26,343
Industrial [Member] | Intersegment Eliminations [Member]
Net Sales	(4,661)	(3,434)
Industrial [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	22,621	24,143
Industrial [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	5,494	5,634
Land Based Transmissions [Member]
Net Sales	58,421	62,697
Land Based Transmissions [Member] | Intersegment Eliminations [Member]
Net Sales	(20,023)	(26,525)
Land Based Transmissions [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	52,441	63,523
Land Based Transmissions [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	26,003	25,699
Marine and Propulsion Systems [Member]
Net Sales	127,243	152,501
Marine and Propulsion Systems [Member] | Intersegment Eliminations [Member]
Net Sales	(48,404)	(46,544)
Marine and Propulsion Systems [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	116,371	139,833
Marine and Propulsion Systems [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	59,276	59,212
Other [Member]
Net Sales	9,463	5,297
Other [Member] | Intersegment Eliminations [Member]
Net Sales	(62)	(48)
Other [Member] | Manufacturing Segment [Member] | Operating Segments [Member]
Net Sales	77	66
Other [Member] | Distribution Segment [Member] | Operating Segments [Member]
Net Sales	$ 9,448	$ 5,279