Concentration of Credit Risk	12 Months Ended
Dec. 30, 2017
Risks And Uncertainties [Abstract]
Concentration of Credit Risk	Note 15 – Concentration of Credit Risk The Company may provide financial assistance in the form of loans to certain independent retailers for inventories, store fixtures and equipment and store improvements. Loans are generally secured by liens on real estate, inventory and/or equipment, personal guarantees and other types of collateral, and are generally repayable over a period of five to ten years. The Company establishes allowances for doubtful accounts based upon periodic assessments of the credit risk of specific customers, collateral value, historical trends and other information. The Company believes that adequate provisions have been recorded for any doubtful accounts. In addition, the Company may guarantee debt and lease obligations of independent retailers. In the event these retailers are unable to meet their debt service payments or otherwise experience an event of default, the Company would be unconditionally liable for the outstanding balance of their debt and lease obligations, which would be due in accordance with the underlying agreements. In the ordinary course of business, the Company may advance funds to certain independent retailers which are earned by the retailers primarily through achieving specified purchase volume requirements, as outlined in their supply agreements with the Company, or in limited instances, for remaining a SpartanNash customer for a specified time period. These advances must be repaid if the purchase volume requirements are not met or if the retailer no longer remains a customer for the specified time period. As of December 30, 2017, the Company has an unearned advanced amount to one independent retailer for an amount representing approximately two percent of the Company’s total assets. The Company’s collateral related to the advanced funds is a security interest in select business assets of the independent retailer’s stores, including select real property assets and other collateral, including a personal guarantee, from the shareholder. Despite the collateral, the Company may be unable to realize the entire unearned portion of the funds advanced to this independent retailer, and accordingly, has established a reserve of $4.9 million related to the advance. During the fourth quarter of 2017, and in the context of a state law receivership proceeding, the customer rationalized its retail store base and entered into a new supply agreement with the Company, and assumed the obligation of the original agreement. Based on the expected cash flows generated from sales to this customer and consideration of the previously mentioned collateral, the Company believes it is adequately reserved as of December 30, 2017. However, if the customer’s future performance and related cash flows are negatively impacted by changes in economic, industry or market conditions, including changes in the business climate and competition, the Company may be unable to realize the remaining unearned portion of the advanced funds. Given the uncertainty regarding the previously mentioned factors that could impact the customer’s future performance, the Company cannot reasonably estimate the additional amount of advanced funds, if any, that should be reserved. The Company estimates that the possible range of loss related to this customer, in excess of the amount currently reserved, is between zero and $25.0 million, depending on the circumstances discussed above. As of December 30, 2017, the Company has guaranteed bank debt for one independent retailer in the amount of $1.5 million. This guarantee, which is secured by certain business assets and personal guarantees of the retailer, represents the maximum undiscounted payments the Company would be required to make in the event of default. The Company believes this independent retailer will be able to perform under the loan agreement and that no payments will be required and no loss will be incurred under the guarantee. The fair value of the obligation assumed under the guarantee is not material. In the ordinary course of business, the Company also subleases and assigns various leases to third parties. As of December 30, 2017, the Company estimates the present value of its maximum potential obligations for subleases and assigned leases to be approximately $6.4 million and $13.8 million, respectively.

Note 15 – Concentration of Credit Risk

The Company may provide financial assistance in the form of loans to certain independent retailers for inventories, store fixtures and equipment and store improvements. Loans are generally secured by liens on real estate, inventory and/or equipment, personal guarantees and other types of collateral, and are generally repayable over a period of five to ten years. The Company establishes allowances for doubtful accounts based upon periodic assessments of the credit risk of specific customers, collateral value, historical trends and other information. The Company believes that adequate provisions have been recorded for any doubtful accounts. In addition, the Company may guarantee debt and lease obligations of independent retailers. In the event these retailers are unable to meet their debt service payments or otherwise experience an event of default, the Company would be unconditionally liable for the outstanding balance of their debt and lease obligations, which would be due in accordance with the underlying agreements.

In the ordinary course of business, the Company may advance funds to certain independent retailers which are earned by the retailers primarily through achieving specified purchase volume requirements, as outlined in their supply agreements with the Company, or in limited instances, for remaining a SpartanNash customer for a specified time period. These advances must be repaid if the purchase volume requirements are not met or if the retailer no longer remains a customer for the specified time period. As of December 30, 2017, the Company has an unearned advanced amount to one independent retailer for an amount representing approximately two percent of the Company’s total assets. The Company’s collateral related to the advanced funds is a security interest in select business assets of the independent retailer’s stores, including select real property assets and other collateral, including a personal guarantee, from the shareholder. Despite the collateral, the Company may be unable to realize the entire unearned portion of the funds advanced to this independent retailer, and accordingly, has established a reserve of $4.9 million related to the advance. During the fourth quarter of 2017, and in the context of a state law receivership proceeding, the customer rationalized its retail store base and entered into a new supply agreement with the Company, and assumed the obligation of the original agreement. Based on the expected cash flows generated from sales to this customer and consideration of the previously mentioned collateral, the Company believes it is adequately reserved as of December 30, 2017. However, if the customer’s future performance and related cash flows are negatively impacted by changes in economic, industry or market conditions, including changes in the business climate and competition, the Company may be unable to realize the remaining unearned portion of the advanced funds. Given the uncertainty regarding the previously mentioned factors that could impact the customer’s future performance, the Company cannot reasonably estimate the additional amount of advanced funds, if any, that should be reserved. The Company estimates that the possible range of loss related to this customer, in excess of the amount currently reserved, is between zero and $25.0 million, depending on the circumstances discussed above.

As of December 30, 2017, the Company has guaranteed bank debt for one independent retailer in the amount of $1.5 million. This guarantee, which is secured by certain business assets and personal guarantees of the retailer, represents the maximum undiscounted payments the Company would be required to make in the event of default. The Company believes this independent retailer will be able to perform under the loan agreement and that no payments will be required and no loss will be incurred under the guarantee. The fair value of the obligation assumed under the guarantee is not material. In the ordinary course of business, the Company also subleases and assigns various leases to third parties. As of December 30, 2017, the Company estimates the present value of its maximum potential obligations for subleases and assigned leases to be approximately $6.4 million and $13.8 million, respectively.