Name:	jack_IncreaseDecreaseInCapitalLeaseObligations
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Period Type:	duration

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

Amount of tangible or intangible assets, including a business or subsidiary of the acquirer transferred by the entity to the former owners of the acquiree. Excludes cash.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

Name:	us-gaap_IncomeTaxesPaid
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Data Type:	xbrli:monetaryItemType
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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.

No definition available.

Name:	us-gaap_IncreaseDecreaseInConstructionPayables
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Data Type:	xbrli:monetaryItemType
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The increase (decrease) during the reporting period in the liability under agreements to repurchase securities that were sold.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

Name:	us-gaap_IncreaseDecreaseInPayablesUnderRepurchaseAgreements
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Period Type:	duration

The amount of cash paid for interest during the period net of cash paid for interest that is capitalized.

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Balance Type:	credit
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- References

No definition available.