Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Dec. 27, 2019	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 525,732	$ 520,533
Accumulated depreciation	(270,507)	(259,830)
Property, plant and equipment, net	255,225	260,703
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment	20,058	19,897
Buildings and related improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	128,376	127,061
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	320,100	318,421
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	8,916	9,055
Software
Property, Plant and Equipment [Line Items]
Property, plant and equipment	25,795	24,835
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 22,487	$ 21,264