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Franchise Rights Acquired, Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($)			3 Months Ended		9 Months Ended		12 Months Ended
	May 05, 2019	May 06, 2018	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018	Dec. 28, 2019	Dec. 29, 2018
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill			$ 152,806,000		$ 152,806,000			$ 152,519,000
Finite-lived intangible assets, aggregate amortization expense			$ 6,973,000	$ 7,213,000	$ 22,014,000	$ 21,453,000
Scenario, Forecast
Goodwill And Intangible Assets Disclosure [Line Items]
Franchise right maturity period							7 years
Brazil
Goodwill And Intangible Assets Disclosure [Line Items]
Reporting unit, percentage of estimated fair value in excess of carrying amount			3.00%		3.00%
Goodwill			$ 4,278,000		$ 4,278,000
NEW ZEALAND
Goodwill And Intangible Assets Disclosure [Line Items]
Reporting units percentage of rights acquired			0.60%		0.60%
Netbook value					$ 4,455,000
United States
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill			$ 98,857,000		98,857,000
Netbook value					671,914,000
Canada
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill			40,442,000		40,442,000
Netbook value					54,456,000
Other Countries
Goodwill And Intangible Assets Disclosure [Line Items]
Goodwill			$ 9,229,000		9,229,000
United Kingdom
Goodwill And Intangible Assets Disclosure [Line Items]
Netbook value					11,072,000
Australia
Goodwill And Intangible Assets Disclosure [Line Items]
Netbook value					$ 6,081,000
Goodwill
Goodwill And Intangible Assets Disclosure [Line Items]
Percentage of goodwill hold by reporting units			97.20%		97.20%
Minimum \| Goodwill
Goodwill And Intangible Assets Disclosure [Line Items]
Reporting unit, percentage of estimated fair value in excess of carrying amount			2.80%		2.80%
Maximum
Goodwill And Intangible Assets Disclosure [Line Items]
Finite-lived intangible assets, estimated useful life (in years)					1 year
Franchise Rights
Goodwill And Intangible Assets Disclosure [Line Items]
Indefinite-lived intangible assets, impairment charges	$ 0	$ 0
Reporting units percentage of rights acquired			99.40%		99.40%
Franchise Rights \| NEW ZEALAND
Goodwill And Intangible Assets Disclosure [Line Items]
Reporting unit, percentage of estimated fair value in excess of carrying amount			3.00%		3.00%
Netbook value					$ 4,455,000
Franchise Rights \| Minimum
Goodwill And Intangible Assets Disclosure [Line Items]
Reporting unit, percentage of estimated fair value in excess of carrying amount			40.00%		40.00%