Operating Segments and Geographic Data (Schedule Of Long-Lived Assets, Net Of Accumulated Depreciation, By Geographic Region) (Details) - USD ($) $ in Thousands	Sep. 27, 2019	Sep. 28, 2018
Revenues from External Customers and Long-Lived Assets [Line Items]
Total long-lived tangible assets, net of accumulated depreciation	$ 537,432	$ 514,182
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	460,370	453,336
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Long-lived assets	$ 77,062	$ 60,846