XML 46 R57.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Impairment and other charges, net Restructuring cost (Details) - USD ($) $ in Thousands | 4 Months Ended
--- | ---
Jan. 19, 2020 | Jan. 20, 2019
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 1,045 | $ 5,840 |
Employee Severance and Related Costs |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | 1,045 | 4,506 |
Strategic Alternative Evaluation |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring costs | $ 0 | $ 1,334 | [1]
[1] | Strategic Alternative Evaluation costs primarily relate to third party advisory services.

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_RestructuringCostAndReserveLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. + References 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 (b) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585 + Details
Name: | us-gaap_RestructuringCosts
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=us-gaap_EmployeeSeveranceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringCostAndReserveAxis=jack_StrategicAlternativeEvaluationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |