Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

Name:	us-gaap_BusinessCombinationIntegrationRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_DepreciationAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

Name:	us-gaap_OperatingIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

+ Details

Name:	us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

+ Details

Name:	us-gaap_RestructuringCostsAndAssetImpairmentCharges
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

+ Details

Name:	us-gaap_SalesRevenueNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_SegmentReportingInformationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_StatementOperatingActivitiesSegmentAxis=us-gaap_SegmentDiscontinuedOperationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=sptn_DistributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=sptn_MilitaryMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=sptn_RetailMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Reporting Segment Information - Schedule of Segment Reporting Information, by Operating Segment (Detail) - USD ($) $ in Thousands	3 Months Ended						4 Months Ended		12 Months Ended
	Dec. 30, 2017	Oct. 07, 2017	Jul. 15, 2017	Dec. 31, 2016	Oct. 08, 2016	Jul. 16, 2016	Apr. 22, 2017	Apr. 23, 2016	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Segment Reporting Information [Line Items]
Net sales	$ 1,924,225	$ 1,906,644	$ 1,894,709	$ 1,828,183	$ 1,800,085	$ 1,827,562	$ 2,402,504	$ 2,278,770	$ 8,128,082	$ 7,734,600	$ 7,651,973
Merger/acquisition and integration	1,070	2,392	622	2,722	2,427	913	4,017	897	8,101	6,959	8,433
Goodwill impairment		189,027							189,027
Restructuring charges (gains) and asset impairment	2,799	35,626	$ (14)	8,402	$ 2,662	$ 5,748	$ 1,021	$ 15,304	39,432	32,116	8,802
Depreciation and amortization									83,240	77,246	83,334
Operating earnings (loss)									(106,316)	108,767	122,875
Capital expenditures									70,906	73,429	79,394
Total Assets	2,055,797			1,930,336					2,055,797	1,930,336
Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Total Assets	3,446			3,249					3,446	3,249
Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									8,128,082	7,734,600	7,651,973
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales									(885,872)	(918,095)	(973,512)
Food Distribution [Member]
Segment Reporting Information [Line Items]
Merger/acquisition and integration									6,244	3,703	2,037
Restructuring charges (gains) and asset impairment									1,317	5,068	(216)
Depreciation and amortization									30,255	21,397	26,127
Operating earnings (loss)									83,296	85,093	78,841
Capital expenditures									25,990	19,075	17,967
Total Assets	1,085,621			776,725					1,085,621	776,725
Food Distribution [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									3,992,192	3,454,541	3,305,094
Food Distribution [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Net sales									(885,872)	(918,095)	(973,512)
Military [Member]
Segment Reporting Information [Line Items]
Merger/acquisition and integration									1,522	1
Restructuring charges (gains) and asset impairment									500	(473)	1,048
Depreciation and amortization									11,626	11,484	12,081
Operating earnings (loss)									7,014	12,160	17,059
Capital expenditures									6,482	6,447	3,768
Total Assets	432,818			395,737					432,818	395,737
Military [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									2,144,022	2,197,014	2,207,161
Retail [Member]
Segment Reporting Information [Line Items]
Merger/acquisition and integration									335	3,255	6,396
Goodwill impairment		$ 189,000							189,027
Restructuring charges (gains) and asset impairment									37,615	27,521	7,970
Depreciation and amortization									41,359	44,365	45,126
Operating earnings (loss)									(196,626)	11,514	26,975
Capital expenditures									38,434	47,907	57,659
Total Assets	$ 533,912			$ 754,625					533,912	754,625
Retail [Member] \| Operating Segments [Member]
Segment Reporting Information [Line Items]
Net sales									$ 1,991,868	$ 2,083,045	$ 2,139,718