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Associate Retirement Plans - Additional Information (Detail) - USD ($)
3 Months Ended 6 Months Ended
Jul. 15, 2017
Jul. 15, 2017
Jul. 16, 2016
Defined Benefit Plan Disclosure [Line Items]      
Pension contributions during last plan year   $ 7,800,000 $ 7,500,000
SpartanNash Company Pension Plan [Member] | Pension Plan [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Net periodic benefit (income) expense $ (200,000) (300,000)  
Standard pension funding carryover   0  
Expected Company contribution for remainder of fiscal year 0 0  
SpartanNash Medical Plan [Member] | Postretirement Health Coverage [Member]      
Defined Benefit Plan Disclosure [Line Items]      
Net periodic benefit (income) expense $ 100,000 $ 200,000