Schedule II - Valuation and Qualifying Accounts - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 30, 2017
Balance, beginning of year	$ 295	$ 201	$ 291
Amounts charged to earnings	(41)	100	(57)
Write-offs, net of recoveries		(6)	(33)
Balance, end of year	$ 254	$ 295	$ 201

Amount of increase (decrease) in valuation and qualifying accounts and reserves from adjustment.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of valuation and qualifying accounts and reserves.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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