XML 75 R59.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Segment Information (Narrative) (Details) $ in Millions	12 Months Ended
	Sep. 28, 2019 USD ($) segment	Sep. 29, 2018 USD ($)	Sep. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	1
Fluid dairy [Member]
Segment Reporting Information [Line Items]
Sales eliminated in consolidation | $	$ 42.1	$ 41.1	$ 45.9

X

- Definition

Intercompany eliminations.

+ References

No definition available.

+ Details

Name:	imkta_IntercompanyEliminations
Namespace Prefix:	imkta_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- 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

X

- Details

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