Discontinued Operations - Income related to the Discontinued Operations (Details) - USD ($) $ in Thousands			12 Months Ended
	May 29, 2019	Nov. 29, 2018	Sep. 30, 2020	Sep. 30, 2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax provision			$ 0	$ 8
Loss from discontinued operations, net of tax			$ 0	(1,267)
Discontinued Operations, Disposed of by Sale | Cable TV Business Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total net sales				13,743
Cost of sales				10,097
Operating, selling, general and administrative expenses				3,412
Other expenses				2
Income from discontinued operations				232
Loss on sale of discontinued operations	$ (3,805)	$ 2,312		(1,491)
Income tax provision				8
Loss from discontinued operations, net of tax				$ (1,267)