Document and Entity Information - shares	9 Months Ended
	Sep. 26, 2020	Oct. 16, 2020
Document and Entity Information
Entity Registrant Name	WINMARK CORPORATION
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 26, 2020
Document Transition Report	false
Entity File Number	000-22012
Entity Incorporation, State or Country Code	MN
Entity Tax Identification Number	41-1622691
Entity Address, Address Line One	605 Highway 169 North, Suite 400
Entity Address, City or Town	Minneapolis
Entity Address, State or Province	MN
Entity Address, Postal Zip Code	55441
City Area Code	763
Local Phone Number	520-8500
Title of 12(b) Security	Common Stock, no par value per share
Trading Symbol	WINA
Security Exchange Name	NASDAQ
Amendment Flag	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		3,740,296
Current Fiscal Year End Date	--12-26
Entity Central Index Key	0000908315
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q3