Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Mar. 27, 2020	Sep. 30, 2019
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 524,165	$ 520,533
Accumulated depreciation	(277,861)	(259,830)
Property, plant and equipment, net	246,304	260,703
Land
Property, Plant and Equipment [Line Items]
Property, plant and equipment	20,053	19,897
Buildings and related improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	128,511	127,061
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment	317,399	318,421
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, plant and equipment	8,941	9,055
Software
Property, Plant and Equipment [Line Items]
Property, plant and equipment	25,974	24,835
Construction in progress
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 23,287	$ 21,264