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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Restructuring Charges and Asset Impairments (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Jan. 01, 2021	Dec. 31, 2021	Jan. 01, 2021	Dec. 27, 2019
Restructuring Cost And Reserve [Line Items]
Restructuring charges and asset impairments		$ 0	$ 10,488,000	$ 4,514,000
Restructuring Reserve	$ 2,292,000	$ 740,000	2,292,000	1,584,000
Impairment of assets	$ 3,900,000		3,885,000	1,180,000
Hackett Institute Enterprise Analytics Program [Member]
Restructuring Cost And Reserve [Line Items]
Impairment of assets				1,200,000
Europe and Australia [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges and asset impairments				$ 3,300,000
Real Estate Leases [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges and asset impairments			4,800,000
Impairment Related Costs [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges and asset impairments			4,800,000
COVID-19 [Member]
Restructuring Cost And Reserve [Line Items]
Restructuring charges and asset impairments			$ 5,700,000