Revenue Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Disaggregation of Revenue
Franchise rental income	$ 58,721	$ 59,918	$ 173,434	$ 176,931
Total revenues	452,242	437,880	1,259,508	1,281,811
Sales at Company-operated restaurants
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	191,946	181,977	522,961	530,724
Franchise royalty revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	109,344	102,267	301,891	299,931
Franchise fees
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	7,476	6,888	19,754	20,302
Advertising funds revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	84,755	86,830	241,468	253,923
Wendy's U.S.
Disaggregation of Revenue
Franchise rental income	0	0	0	0
Total revenues	374,895	359,353	1,037,194	1,051,994
Wendy's U.S. \| Sales at Company-operated restaurants
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	191,946	181,977	522,961	530,724
Wendy's U.S. \| Franchise royalty revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	98,128	90,791	271,082	266,599
Wendy's U.S. \| Franchise fees
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	5,651	5,199	16,244	15,867
Wendy's U.S. \| Advertising funds revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	79,170	81,386	226,907	238,804
Wendy's International
Disaggregation of Revenue
Franchise rental income	0	0	0	0
Total revenues	17,264	17,931	46,739	50,959
Wendy's International \| Sales at Company-operated restaurants
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Wendy's International \| Franchise royalty revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	11,216	11,476	30,809	33,332
Wendy's International \| Franchise fees
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	463	1,011	1,369	2,508
Wendy's International \| Advertising funds revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	5,585	5,444	14,561	15,119
Global Real Estate & Development
Disaggregation of Revenue
Franchise rental income	58,721	59,918	173,434	176,931
Total revenues	60,083	60,596	175,575	178,858
Global Real Estate & Development \| Sales at Company-operated restaurants
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Global Real Estate & Development \| Franchise royalty revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	0	0	0	0
Global Real Estate & Development \| Franchise fees
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	1,362	678	2,141	1,927
Global Real Estate & Development \| Advertising funds revenue
Disaggregation of Revenue
Revenue from Contract with Customer, Excluding Assessed Tax	$ 0	$ 0	$ 0	$ 0

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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