Leases - Schedule of Maturities of Lease Liabilities Under Operating and Finance Leases (Detail) - USD ($) $ in Thousands	Dec. 28, 2024	Dec. 30, 2023
Leases [Abstract]
Operating Leases, 2025	$ 69,639
Operating Leases, 2026	64,012
Operating Leases, 2027	57,479
Operating Leases, 2028	48,632
Operating Leases, 2029	40,269
Operating Leases, Thereafter	186,836
Operating Leases, Total	466,867
Operating Leases, Less interest	112,254
Total operating lease liabilities	354,613	$ 268,097
Operating Leases, Less current portion	49,562	41,979
Operating Leases, Long-term lease liabilities	305,051	226,118
Finance Leases, 2025	19,887
Finance Leases, 2026	19,109
Finance Leases, 2027	18,113
Finance Leases, 2028	17,529
Finance Leases, 2029	16,573
Finance Leases, Thereafter	79,073
Finance Leases, Total	170,284
Finance Leases, Less interest	44,506
Total finance lease liabilities	125,778	74,639
Finance Leases, Less current portion	12,141	7,739
Finance Leases, Long-term lease liabilities	113,637	$ 66,900
Operating and Finance Leases, 2025	89,526
Operating and Finance Leases, 2026	83,121
Operating and Finance Leases, 2027	75,592
Operating and Finance Leases, 2028	66,161
Operating and Finance Leases, 2029	56,842
Operating and Finance Leases, Thereafter	265,909
Operating and Finance Leases, Total	637,151
Operating and Finance Leases, Less interest	156,760
Operating and Finance Leases, Present value of lease liabilities	480,391
Operating and Finance Leases, Less current portion	61,703
Operating and Finance Leases, Long-term lease liabilities	$ 418,688

Operating and finance lease liability.

No definition available.

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- Definition

Operating and finance lease liability current.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability noncurrent.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due after year five.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease, liability, payments, due next twelve months.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due year five.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due year four.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due year three.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability payments due year two.

+ References

No definition available.

+ Details

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- Definition

Operating and finance lease liability undiscounted excess amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	sptn_
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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479041/842-20-45-1

+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payments for finance lease.

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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- Definition

Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

+ Details

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- Definition

Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

+ References

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- References

No definition available.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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- Definition

Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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