Contingencies and Legal Matters (Details) (USD $) In Millions, unless otherwise specified	4 Months Ended
	Jan. 18, 2015
Guarantees [Abstract]
Loss Contingency, Damages Sought, Value	$ 45.0
Contingencies and Legal Matters	CONTINGENCIES AND LEGAL MATTERS Legal matters — The Company assesses contingencies, including litigation contingencies, to determine the degree of probability and range of possible loss for potential accrual in its financial statements. An estimated loss contingency is accrued in the financial statements if it is probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Because litigation is inherently unpredictable, assessing contingencies is highly subjective and requires judgments about future events. When evaluating litigation contingencies, we may be unable to provide a meaningful estimate due to a number of factors, including the procedural status of the matter in question, the availability of appellate remedies, insurance coverage related to the claim or claims in question, the presence of complex or novel legal theories, and/or the ongoing discovery and development of information important to the matter. In addition, damage amounts claimed in litigation against us may be unsupported, exaggerated or unrelated to possible outcomes, and as such are not meaningful indicators of our potential liability or financial exposure. The Company regularly reviews contingencies to determine the adequacy of the accruals and related disclosures. The ultimate amount of loss may differ from these estimates. Gessele v. Jack in the Box Inc. — In August 2010, five former employees instituted litigation in federal court in Oregon alleging claims under the federal Fair Labor Standards Act and Oregon wage and hour laws. The plaintiffs alleged that the Company failed to pay non-exempt employees for certain meal breaks and improperly made payroll deductions for shoe purchases and for workers’ compensation expenses. In April 2014, the district court granted our motion for summary judgment, and dismissed all claims without prejudice to re-filing in state court. In July 2014, the plaintiffs re-filed similar claims, and additional claims relating to timing of final pay and related wage and hour claims involving employees of a franchisee, in Oregon state court. The amended complaint seeks damages of $45.0 million but does not provide a basis for that amount. In fiscal 2012, we accrued for a single claim for which we believe a loss is both probable and estimable; this accrued loss contingency did not have a material effect on our results of operations. We have not established a loss contingency accrual for those claims as to which we believe liability is not probable or estimable, and we plan to vigorously defend against this lawsuit. Nonetheless, an unfavorable resolution of this matter in excess of our current accrued loss contingencies could have a material adverse effect on our business, results of operations, liquidity or financial condition. Other legal matters — In addition to the matter described above, the Company is subject to normal and routine litigation brought by former, current or prospective employees, customers, franchisees, vendors, landlords, shareholders or others. We intend to defend ourselves in any such matters. Some of these matters may be covered, at least in part, by insurance. Our insurance liability (undiscounted) and reserves are established in part by using independent actuarial estimates of expected losses for reported claims and for estimating claims incurred but not reported. As of January 18, 2015, our estimated liability for general liability and workers’ compensation claims exceeded our self-insurance retention limits by $24.6 million. We expect to be fully covered for these amounts by surety bond issuers or our insurance providers. Although the Company currently believes that the ultimate determination of liability in connection with legal claims pending against it, if any, in excess of amounts already provided for these matters in the consolidated financial statements will not have a material adverse effect on our business, the Company’s annual results of operations, liquidity or financial position, it is possible that our results of operations, liquidity, or financial position could be materially affected in a particular future reporting period by the unfavorable resolution of one or more of these matters or contingencies during such period. Lease guarantees — In connection with the sale of the distribution business, we have assigned the leases at two of our distribution centers to third parties. Under these agreements, which expire in 2015 and 2017, we remain secondarily liable for the lease payments for which we were responsible under the original lease. As of January 18, 2015, the amount remaining under these lease guarantees totaled $1.8 million. We have not recorded a liability for the guarantees as the likelihood of the third party defaulting on the assignment agreements was deemed to be less than probable.
General liability and workers' comp estimated claims to be paid by insurance providers	24.6
number of distribution center leases assigned to third parties	2
Guarantor obligations, maximum exposure, Undiscounted	$ 1.8