Document and Entity Information - shares	9 Months Ended
	Oct. 03, 2021	Nov. 04, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Oct. 03, 2021
Entity File Number	001-33994
Entity Registrant Name	INTERFACE INC
Entity Incorporation, State or Country Code	GA
Entity Tax Identification Number	58-1451243
Entity Address, Address Line One	1280 West Peachtree Street
Entity Address, City or Town	Atlanta
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30309
City Area Code	770
Local Phone Number	437-6800
Title of 12(b) Security	Common Stock, $0.10 Par Value Per Share
Trading Symbol	TILE
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		59,054,937
Entity Central Index Key	0000715787
Amendment Flag	false
Current Fiscal Year End Date	--01-02
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2021