Document And Entity Information (USD $)	3 Months Ended
	Sep. 30, 2011	Oct. 28, 2011	Dec. 31, 2010
Entity Registrant Name	TWIN DISC INC
Entity Central Index Key	0000100378
Current Fiscal Year End Date	--06-30
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	No
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 248,814,593
Entity Common Stock, Shares Outstanding		11,429,487
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q1
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2011