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Associate Retirement Plans - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
4 Months Ended 12 Months Ended
Apr. 25, 2015
Apr. 19, 2014
Jan. 03, 2015
SpartanNash Pension Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Standard pension funding carryover $ 0.4us-gaap_PensionContributions
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= sptn_SpartanNashPensionPlanMember
   
Central States, Southeast and Southwest Areas Pension Fund [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Pension contributions during plan year $ 4.2us-gaap_MultiemployerPlansPlanContributions
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= sptn_CentralStatesSoutheastAndSouthwestAreasPensionFundMember
$ 4.1us-gaap_MultiemployerPlansPlanContributions
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= sptn_CentralStatesSoutheastAndSouthwestAreasPensionFundMember
$ 12.9us-gaap_MultiemployerPlansPlanContributions
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= sptn_CentralStatesSoutheastAndSouthwestAreasPensionFundMember
Maximum company contribution as percentage of total employer contributions     5.00%sptn_MultiemployerPlansFundAdministratorsPercentageOfAggregateEmployerContributionsMaximum
/ us-gaap_DefinedBenefitPlansDisclosuresDefinedBenefitPlansAxis
= sptn_CentralStatesSoutheastAndSouthwestAreasPensionFundMember