Defined benefit plan pre-tax settlement charge.

No definition available.

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Balance Type:	debit
Period Type:	duration

- Definition

Defined benefit plan, termination date.

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

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Balance Type:	debit
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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

Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

+ References

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-Publisher FASB
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Balance Type:	debit
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- Definition

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

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of contributions made to multiemployer plan by all employers who participate in plan.

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- Details

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Associate Retirement Plans - Additional Information (Detail) - USD ($)		4 Months Ended
	Feb. 28, 2018	Apr. 20, 2019	Apr. 21, 2018
Defined Benefit Plan Disclosure [Line Items]
Pension contributions during last plan year		$ 4,800,000	$ 4,500,000
Pension Plan or Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Frozen pension plan, termination date		Jul. 31, 2018
Standard pension funding carryover		$ 0
Pension Plan or Plan [Member] \| Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
One-time, pre-tax settlement charge	$ 20,000,000
Pension Plan or Plan [Member] \| Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
One-time, pre-tax settlement charge	$ 21,000,000
Expected Company contribution for remainder of fiscal year		500,000
Retiree Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected Company contribution for remainder of fiscal year		400,000
SpartanNash Company Pension Plan [Member] \| Pension Plan or Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense		400,000	(100,000)
SpartanNash Retiree Medical Plan [Member] \| Retiree Medical Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit (income) expense		$ 100,000	$ 100,000