Valuation and Qualifying Accounts (Details) - Allowance For Uncollectible Accounts [Member] - USD ($) $ in Thousands		12 Months Ended
		Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Period		$ 1,946	$ 1,455	$ 1,967
Charged to Costs and Expenses		1,144	2,176	1,145
Charged to Accounts
Deductions	[1]	1,000	1,685	1,657
Balance at End of Period		$ 2,090	$ 1,946	$ 1,455

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