Goodwill and Other Intangible Assets (Schedule of Changes in Carrying Amounts of Goodwill) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 28, 2019
Goodwill [Roll Forward]
Beginning Balance	$ 883,158	$ 847,544
Goodwill, Acquired During Period	33,709	37,071
Goodwill, Written off Related to Sale of Business Unit	(7,692)
Goodwill, Other Increase (Decrease)	744
Foreign currency translation adjustment and other	4,601	(1,457)
Ending Balance	914,520	883,158
Domestic Segment [Member]
Goodwill [Roll Forward]
Beginning Balance	819,735	782,664
Goodwill, Acquired During Period	33,709	37,071
Goodwill, Written off Related to Sale of Business Unit	0
Goodwill, Other Increase (Decrease)	744
Foreign currency translation adjustment and other	0	0
Ending Balance	854,188	819,735
International Segment [Member]
Goodwill [Roll Forward]
Beginning Balance	63,423	64,880
Goodwill, Acquired During Period	0	0
Goodwill, Written off Related to Sale of Business Unit	(7,692)
Goodwill, Other Increase (Decrease)	0
Foreign currency translation adjustment and other	4,601	(1,457)
Ending Balance	$ 60,332	$ 63,423

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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-Name Accounting Standards Codification
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