Segment Information Reconciliation of Profit from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 81,348	$ 79,023	$ 190,741	$ 225,862
Advertising funds deficit	(1,140)	(1,053)	(3,547)	(3,108)
Unallocated general and administrative	(47,322)	(46,169)	(147,553)	(146,266)
Depreciation and amortization	(32,966)	(33,306)	(98,726)	(97,975)
System optimization gains, net	23	1,040	2,333	1,162
Reorganization and realignment costs	(3,375)	(403)	(10,196)	(4,771)
Impairment on long-lived assets	(23)	0	(4,727)	(1,684)
Unallocated other operating income, net	2,748	2,392	6,076	9,377
Interest expense, net	(29,086)	(27,930)	(86,696)	(86,943)
Loss on early extinguishment of debt	0	0	0	(7,150)
Other income, net	181	2,218	1,113	7,165
Income before income taxes	52,443	53,311	105,158	138,934
Corporate and Other
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Unallocated general and administrative	(21,424)	(18,254)	(68,594)	(59,606)
Unallocated other operating income, net	49	(22)	140	115
Operating Segments
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	140,204	131,021	374,058	391,729
Operating Segments \| Wendy's U.S.
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	108,297	98,342	283,261	290,969
Advertising funds deficit	(6,153)		(8,338)
Operating Segments \| Wendy's International
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	6,567	6,271	15,256	17,500
Operating Segments \| Global Real Estate & Development
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 25,340	$ 26,408	$ 75,541	$ 83,260

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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