Significant Accounting Policies - Noncontrolling Interests and Foreign Currency Translation (Details) $ in Thousands		3 Months Ended
	Jun. 15, 2018 USD ($) restaurant	Jul. 01, 2018 USD ($) restaurant	Dec. 27, 2020 entity restaurant	Dec. 29, 2019 restaurant entity
Noncontrolling Interests
Number of joint ventures having noncontrolling interests | entity			4	4
Stores in Beijing and Tianjin, China
Noncontrolling Interests
Number of restaurants divested	34	34
Reversal of accumulated other comprehensive income related to foreign currency translation | $	$ 1,300	$ 1,300
Joint ventures
Noncontrolling Interests
Number of Restaurants			188	192