Name:	jack_IncreaseDecreaseInCapitalLeaseObligations
Namespace Prefix:	jack_
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Increase (decrease) in dividends accrued or converted to stock equivalents, adjustment to dividends paid, financing activities

No definition available.

Name:	jack_Increasedecreaseindividendsaccruedorconvertedtostockequivalents
Namespace Prefix:	jack_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The non-cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

No definition available.

Name:	jack_Noncashproceedsfromdivestitureofbusiness
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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The increase during the period in capital lease obligations due to entering into new capital leases.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4313-108586

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

Name:	us-gaap_CapitalLeaseObligationsIncurred
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The increase (decrease) during the reporting period of obligations, not classified as trade payables, incurred and payable for the acquisition of merchandise, materials, supplies, and services pertaining to construction projects.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

The increase (decrease) during the reporting period in the liability under agreements to repurchase securities that were sold.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- References

No definition available.