Schedule II - Valuation and Qualifying Accounts - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Oct. 01, 2016
Balance, beginning of year	$ 201	$ 291	$ 638
Amounts charged to earnings	100	(57)	(244)
Write-offs, net of recoveries	(6)	(33)	(103)
Balance, end of year	$ 295	$ 201	$ 291