Reporting Segment And Geographic Information (Schedule Of Long-Lived Assets) (Details) - USD ($) $ in Millions	Dec. 29, 2017	Dec. 30, 2016
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, Net	$ 174.0	$ 144.2
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, Net	131.7	120.4
Europe [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, Net	33.1	15.3
Asia Pacific And Other Non-US Countries [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Property and equipment, Net	$ 9.2	$ 8.5