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Commitments and Contingencies - Additional Information (Detail) - Employer | Jul. 09, 2021 | Jul. 17, 2021
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Commitments And Contingencies Disclosure [Abstract] |  |
Number of employers contributing to plan |  | 1
Multiemployer plan number of years relief from risk of insolvency | 30 years |

X
- Definition Multiemployer plan number of years relief from risk of insolvency. + References No definition available. + Details
Name: | sptn_MultiemployerPlanNumberOfYearsReliefFromRiskOfInsolvency
Namespace Prefix: | sptn_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of employers. + References No definition available. + Details
Name: | sptn_NumberOfEmployers
Namespace Prefix: | sptn_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

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- References No definition available. + Details
Name: | us-gaap_CommitmentsAndContingenciesDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration