Note M - Earnings Per Share - Components of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Mar. 26, 2021	Dec. 25, 2020	Sep. 25, 2020	Mar. 27, 2020	Dec. 27, 2019	Sep. 27, 2019	Mar. 26, 2021	Mar. 27, 2020
Net loss	$ 166	$ (4,280)	$ (3,937)	$ (25,176)	$ (6,466)	$ (6,293)	$ (8,051)	$ (37,935)
Less: Net earnings attributable to noncontrolling interest	(72)			(54)			(147)	(122)
Less: Undistributed earnings attributable to unvested shares	0			0			0	0
Net income (loss) available to Twin Disc shareholders	$ 94			$ (25,230)			$ (8,198)	$ (38,057)
Weighted average shares outstanding - basic (in shares)	13,269			13,175			13,240	13,147
Net income (loss) per share - basic (in dollars per share)	$ 0.01			$ (1.92)			$ (0.62)	$ (2.89)
Net income (loss) available to Twin Disc shareholders	$ 94			$ (25,230)			$ (8,198)	$ (38,057)
Effect of dilutive stock awards (in shares)	26			0			0	0
Weighted average shares outstanding - diluted (in shares)	13,295			13,175			13,240	13,147
Net income (loss) per share - diluted (in dollars per share)	$ 0.01			$ (1.92)			$ (0.62)	$ (2.89)