Gain realized related to refund

No definition available.

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- Definition

Payment To Retired Participants

+ References

No definition available.

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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.

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

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- Definition

Amount of increase (decrease) in obligation for pension and other postretirement benefits. Includes, but is not limited to, defined benefit and defined contribution plans.

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- Definition

Amount of contribution received by multiemployer pension plan from all employers participating in multiemployer pension plan determined to be individually significant.

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Associate Retirement Plans - Additional Information (Detail) - USD ($) $ in Millions			3 Months Ended		4 Months Ended	6 Months Ended
	Jul. 01, 2023	Jul. 01, 2022	Jul. 15, 2023	Jul. 16, 2022	Apr. 22, 2023	Jul. 15, 2023	Jul. 16, 2022
Defined Benefit Plan Disclosure [Line Items]
Gain realized related to refund					$ 0.2
Pension contributions during last plan year			$ 3.3	$ 3.1		$ 7.6	$ 6.9
Retiree Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense			0.8			1.8
Increase (Decrease) in obligations						6.6
SpartanNash Retiree Medical Plan Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense	$ 0.3	$ 0.7
Payment to retired participants	$ 1.3	$ 2.0
SpartanNash Retiree Medical Plan Plan [Member] \| Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense			$ 0.6	$ 0.7		$ 1.5	$ 0.9