Commitments and Contingencies	9 Months Ended
Oct. 06, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 7 – Commitments and Contingencies The Company is engaged from time-to-time in routine legal proceedings incidental to its business. The Company does not believe that these routine legal proceedings, taken as a whole, will have a material impact on its business or financial condition. While the ultimate effect of such actions cannot be predicted with certainty, management believes that their outcome will not result in an adverse effect on the Company’s consolidated financial position, operating results or liquidity. From time to time, the Company may advance funds to 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 October 6, 2018, the Company has an unearned advance 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 October 6, 2018. 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, which should be reserved. The Company estimates that the possible range of loss related to this customer is between zero and $25.0 million, depending on the circumstances discussed above. The Company contributes to the Central States Southeast and Southwest Pension Fund (“Central States Plan” or “the Plan”), a multi-employer pension plan, based on obligations arising from its collective bargaining agreements (“CBAs”) in Bellefontaine, Ohio, Lima, Ohio, and Grand Rapids, Michigan covering its supply chain associates at those locations. This Plan provides retirement benefits to participants based on their service to contributing employers. The benefits are paid from assets held in trust for that purpose. Trustees are appointed by contributing employers and unions; however, SpartanNash is not a trustee. The trustees typically are responsible for determining the level of benefits to be provided to participants, as well as for such matters as the investment of the assets and the administration of the plan. The Company currently contributes to the Central States Plan under the terms outlined in the “Primary Schedule” of Central States’ Rehabilitation Plan or those outlined in the “Default Schedule.” Both the Primary and Default schedules require varying increases in employer contributions over the previous year’s contribution. Increases are set within the CBAs and vary by location. The Plan continues to be in red zone status, and according to the Pension Protection Act (“PPA”), is considered to be in “critical and declining” zone status. Among other factors, plans in the “critical and declining” zone are generally less than 65% funded and are projected to become insolvent within the next 15 years (or 20 years depending on the ratio of active-to-inactive participants). Based on the most recent information available to the Company, management believes that the present value of actuarial accrued liabilities in this multi-employer plan significantly exceeds the value of the assets held in trust to pay benefits. Because SpartanNash is one of a number of employers contributing to this plan, it is difficult to ascertain what the exact amount of the underfunding would be. Management is not aware of any significant change in funding levels since December 30, 2017. To reduce this underfunding, management expects increases in expense as a result of required incremental multi-employer pension plan contributions in future years. Any adjustment for withdrawal liability will be recorded when it is probable that a liability exists and can be reasonably determined.

Note 7 – Commitments and Contingencies

The Company is engaged from time-to-time in routine legal proceedings incidental to its business. The Company does not believe that these routine legal proceedings, taken as a whole, will have a material impact on its business or financial condition. While the ultimate effect of such actions cannot be predicted with certainty, management believes that their outcome will not result in an adverse effect on the Company’s consolidated financial position, operating results or liquidity.

From time to time, the Company may advance funds to 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 October 6, 2018, the Company has an unearned advance 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 October 6, 2018. 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, which should be reserved. The Company estimates that the possible range of loss related to this customer is between zero and $25.0 million, depending on the circumstances discussed above.

The Company contributes to the Central States Southeast and Southwest Pension Fund (“Central States Plan” or “the Plan”), a multi-employer pension plan, based on obligations arising from its collective bargaining agreements (“CBAs”) in Bellefontaine, Ohio, Lima, Ohio, and Grand Rapids, Michigan covering its supply chain associates at those locations. This Plan provides retirement benefits to participants based on their service to contributing employers. The benefits are paid from assets held in trust for that purpose. Trustees are appointed by contributing employers and unions; however, SpartanNash is not a trustee. The trustees typically are responsible for determining the level of benefits to be provided to participants, as well as for such matters as the investment of the assets and the administration of the plan. The Company currently contributes to the Central States Plan under the terms outlined in the “Primary Schedule” of Central States’ Rehabilitation Plan or those outlined in the “Default Schedule.” Both the Primary and Default schedules require varying increases in employer contributions over the previous year’s contribution. Increases are set within the CBAs and vary by location. The Plan continues to be in red zone status, and according to the Pension Protection Act (“PPA”), is considered to be in “critical and declining” zone status. Among other factors, plans in the “critical and declining” zone are generally less than 65% funded and are projected to become insolvent within the next 15 years (or 20 years depending on the ratio of active-to-inactive participants). Based on the most recent information available to the Company, management believes that the present value of actuarial accrued liabilities in this multi-employer plan significantly exceeds the value of the assets held in trust to pay benefits. Because SpartanNash is one of a number of employers contributing to this plan, it is difficult to ascertain what the exact amount of the underfunding would be. Management is not aware of any significant change in funding levels since December 30, 2017. To reduce this underfunding, management expects increases in expense as a result of required incremental multi-employer pension plan contributions in future years. Any adjustment for withdrawal liability will be recorded when it is probable that a liability exists and can be reasonably determined.