Document and Entity Information - shares	6 Months Ended
	Jul. 11, 2020	Aug. 11, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jul. 11, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Trading Symbol	SPTN
Entity Registrant Name	SPARTANNASH COMPANY
Entity Central Index Key	0000877422
Current Fiscal Year End Date	--01-02
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		35,833,252
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity File Number	000-31127
Entity Tax Identification Number	38-0593940
Entity Address, Address Line One	850 76th Street, S.W.
Entity Address, Address Line Two	P.O. Box 8700
Entity Address, City or Town	Grand Rapids
Entity Address, State or Province	MI
Entity Address, Postal Zip Code	49518
City Area Code	616
Local Phone Number	878-2000
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	MI
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, no par value
Security Exchange Name	NASDAQ