| Document and Entity Information | May 26, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | May 26, 2020 |
| Entity Registrant Name | SpartanNash Company |
| Entity Central Index Key | 0000877422 |
| Entity Emerging Growth Company | false |
| Entity File Number | 000-31127 |
| Entity Incorporation, State or Country Code | MI |
| 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 | 49518-8700 |
| City Area Code | 616 |
| Local Phone Number | 878-2000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of each class | Common Stock, no par value |
| Trading Symbol | SPTN |
| Name of each exchange on which registered | NASDAQ |
