Document and Entity Information - USD ($)	12 Months Ended
	Dec. 28, 2019	Mar. 09, 2020	Jun. 29, 2019
Document and Entity Information
Entity Registrant Name	WINMARK CORP
Entity Central Index Key	0000908315
Document Type	10-K
Document Period End Date	Dec. 28, 2019
Amendment Flag	false
Current Fiscal Year End Date	--12-28
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Public Float			$ 339,792,677
Entity Common Stock, Shares Outstanding		3,648,753
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false