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Associate Retirement Plans - Summary of Actual Assets Allocation (Parenthetical) (Detail)
12 Months Ended
Dec. 31, 2016
Jan. 02, 2016
Defined Benefit Plan Disclosure [Line Items]    
Target plan asset allocations 100.00%  
Equity securities [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Target plan asset allocations 20.00%  
SpartanNash Company Pension Plan [Member] | Equity securities [Member]    
Defined Benefit Plan Disclosure [Line Items]    
Target plan asset allocations   20.00%