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The number of franchises purchased during the period when there are significant changes in franchisor-owned outlets or franchised outlets during the period.

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Subsequent Events (Details) $ / shares in Units, $ in Millions			3 Months Ended	4 Months Ended
	Feb. 18, 2022 $ / shares	Feb. 11, 2022 USD ($)	Apr. 17, 2022 restaurant	Jan. 23, 2022 restaurant $ / shares	Jan. 17, 2021 restaurant $ / shares
Subsequent Event [Line Items]
Cash dividend (in USD per share) \| $ / shares				$ 0.44	$ 0.40
Number of restaurants acquired from franchisees \| restaurant				4	4
Subsequent Event
Subsequent Event [Line Items]
Cash dividend (in USD per share) \| $ / shares	$ 0.44
Number of restaurants acquired from franchisees \| restaurant			9
Subsequent Event \| Series 2022-1 Class A-2-I Notes \| Senior Notes
Subsequent Event [Line Items]
Debt instrument, face amount		$ 550.0
Stated interest rate		3.445%
Subsequent Event \| Series 2022-1 Class A-2-II Notes \| Senior Notes
Subsequent Event [Line Items]
Debt instrument, face amount		$ 550.0
Stated interest rate		4.136%
Subsequent Event \| Series 2019-1 Class A-2-I Notes \| Senior Notes
Subsequent Event [Line Items]
Extinguishment of debt		$ 570.7
Subsequent Event \| Series 2022-1 Class A-1 Notes \| Senior Notes \| Forecast
Subsequent Event [Line Items]
Debt instrument, face amount		150.0
Subsequent Event \| Series 2019-1 Class A-1 Notes \| Senior Notes \| Forecast
Subsequent Event [Line Items]
Extinguishment of debt		$ 150.0