Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017	Dec. 25, 2015	Dec. 26, 2014
Allowance for Doubtful Accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, beginning of the year	$ 4,344	$ 5,160	$ 5,902	$ 7,603
Charged to expense	6,903	8,171	7,132
Release of allowance or Write-offs	(7,719)	(8,913)	(8,833)
Balance, end of the year	4,344	5,160	5,902
Allowance for Receivable from Insurance Provider
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, beginning of the year	3,778	4,019	3,874	3,933
Charged to expense	1,153	207	48
Release of allowance or Write-offs	(1,394)	(62)	(107)
Balance, end of the year	3,778	4,019	3,874
Valuation Allowance of Deferred Tax Assets
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance, beginning of the year	2,508	2,266	3,227	$ 2,844
Charged to expense	2	579	383
Transition to the U.S. Tax Cuts and Jobs Act	240	0	0
Release of allowance or Write-offs	0	(1,540)	0
Balance, end of the year	$ 2,508	$ 2,266	$ 3,227

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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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Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

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