Composition Of Certain Financial Statement Captions (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 29, 2017	Sep. 30, 2016
Composition Of Certain Financial Statement Captions [Line Items]
Raw materials	$ 6,812	$ 3,526
Document Period End Date	Sep. 29, 2017
Other Noncurrent Assets [Member]
Composition Of Certain Financial Statement Captions [Line Items]
Raw materials	$ 1,800	$ 1,600