Schedule II - Valuation and Qualifying Accounts and Reserves (Details) - Allowance for Doubtful Accounts [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 28, 2018	Dec. 29, 2017	Dec. 30, 2016
Valuation And Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 2,601	$ 2,574	$ 1,881
Charge to Revenue/Expense	373	49	744
Write-offs	(1,533)	(22)	(51)
Balance at End of Year	$ 1,441	$ 2,601	$ 2,574

Amount of increase in valuation and qualifying accounts and reserves from charge to cost and expense.

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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration