Valuation and Qualifying Accounts (Details) - Allowance For Uncollectible Accounts [Member] - USD ($) $ in Thousands		12 Months Ended
		Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period		$ 2,090	$ 1,946	$ 1,455
Charged to Costs and Expenses		1,975	1,144	2,176
Charged to Accounts
Deductions	[1]	1,308	1,000	1,685
Balance at End of Period		$ 2,757	$ 2,090	$ 1,946

[1] Deductions are uncollectible accounts written off, net of recoveries.