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Organization and Other Matters - Additional Information (Detail) $ in Thousands	1 Months Ended	9 Months Ended
	Apr. 30, 2016 USD ($)	Sep. 25, 2016 USD ($) State Subsidiary JointVenture	Sep. 27, 2015 USD ($)	Dec. 27, 2015 USD ($)
Nature Of Business And Basis Of Presentation [Line Items]
Number of sandwich works and shops operates or franchises states | State		29
Purchase price of transitioned franchise shop	$ 1,100	$ 1,108	$ 333
Goodwill		$ 2,222		$ 1,428
Number of wholly owned subsidiaries | Subsidiary		8
Number of joint ventures | JointVenture		5
Minimum [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Ownership interest rate		51.00%
Maximum [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Ownership interest rate		80.00%
Franchise-Operated Shops [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Goodwill	$ 800

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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