Reporting Segment And Geographic Information (Narrative) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Jan. 01, 2021
Segment Reporting Information [Line Items]
Property and equipment, net	$ 233.2	$ 251.8
United States
Segment Reporting Information [Line Items]
Property and equipment, net	171.3	200.3
Europe
Segment Reporting Information [Line Items]
Property and equipment, net	$ 44.8	$ 41.0

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant