Segment Information Reconciliation of Profit from Segments to Consolidated (Details) - USD ($) $ in Thousands	3 Months Ended
Apr. 04, 2021	Mar. 29, 2020
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 83,122	$ 48,732
Advertising funds deficit	(1,264)	(1,387)
Unallocated general and administrative	(52,622)	(51,639)
Depreciation and amortization	(31,542)	(31,046)
System optimization gains, net	516	323
Reorganization and realignment costs	(4,934)	(3,910)
Impairment on long-lived assets	(635)	(4,587)
Unallocated other operating income, net	3,476	1,932
Interest expense, net	(28,786)	(28,525)
Other income, net	129	1,076
Income before income taxes	54,465	21,283
Corporate and Other
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Unallocated general and administrative	(25,107)	(24,119)
Unallocated other operating income, net	64	45
Operating Segments
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	146,024	113,413
Operating Segments \| Wendy's U.S.
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	112,087	81,828
Advertising funds deficit	(3,534)
Operating Segments \| Wendy's International
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	7,684	5,095
Operating Segments \| Global Real Estate & Development
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 26,253	$ 26,490

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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