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Associate Retirement Plans - Summary of Actual Assets Allocation (Parenthetical) (Detail) | 12 Months Ended
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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%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Target allocation of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920 + Details
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- Details
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