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Commitments, Contingencies and Legal Matters (Additional Information) (Details) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Aug. 31, 2010 former_employee | Sep. 27, 2020 USD ($) | Sep. 29, 2019 USD ($)
Loss Contingencies [Line Items] |  |  |
Purchase commitment completion period |  | 5 years |
Long-term purchase commitment amount |  | $ 62,100,000 |
Information technology services, early contract termination fees |  | 0 |
Unconditional purchase obligations for information technology services |  | $ 11,300,000 |
Unrecorded purchase obligation period for information technology services |  | 3 years |
Estimated litigation liability |  | $ 3,800,000 | $ 10,000,000.0
Gessele v. Jack in the Box Inc. |  |  |
Loss Contingencies [Line Items] |  |  |
Number of former employees who instituted litigation | former_employee | 5 |  |

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- Definition Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.25) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 55 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=116646759&loc=d3e15243-108350 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349 + Details
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