Capital Assets (Property and Equipment) (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Sep. 28, 2019
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 300,027	$ 295,569
Less: Accumulated depreciation	(198,035)	(194,486)
Total property and equipment, net	101,992	101,083
Land and improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	3,955	3,949
Buildings and improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	68,349	64,140
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 227,723	224,684
Assets held under capital leases
Property, Plant and Equipment [Line Items]
Total property and equipment		$ 2,796