Segment Information Reconciliation of Profit from Segments to Consolidated (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 02, 2022	Jan. 03, 2021	Dec. 29, 2019
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 366,960	$ 269,308	$ 262,579
Unallocated franchise support and other costs	(42,900)	(26,464)	(43,686)
Advertising funds surplus	2,770	2,904	1,337
Unallocated general and administrative	(242,970)	(206,876)	(200,206)
Depreciation and amortization	(125,540)	(132,775)	(131,693)
System optimization gains, net	33,545	3,148	1,283
Reorganization and realignment costs	(8,548)	(16,030)	(16,965)
Impairment of long-lived assets	(2,251)	(8,037)	(6,999)
Unallocated other operating income, net	14,468	8,397	11,418
Interest expense, net	(109,185)	(117,737)	(115,971)
Loss on early extinguishment of debt	(17,917)	0	(8,496)
Investment income (loss), net	39	(225)	25,598
Other income, net	681	1,449	7,771
Income before income taxes	240,578	152,795	171,481
Corporate and Other
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Unallocated franchise support and other costs	(753)	0	0
Unallocated general and administrative	(116,273)	(94,256)	(81,230)
Unallocated other operating income, net	394	190	291
Operating Segments
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	583,616	514,164	496,555
Operating Segments | Wendy's U.S.
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	450,117	393,314	369,193
Advertising funds surplus	(25,000)	(14,600)
Operating Segments | Wendy's International
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	27,386	20,119	20,246
Operating Segments | Global Real Estate & Development
Segment Reporting, Reconciling Item for Profit from Segment to Consolidated
Segment profit	$ 106,113	$ 100,731	$ 107,116