SCHEDULE II: VALUATION AND QUALIFYING ACCOUNTS (Details) - Deferred tax asset valuation allowance - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2018	Dec. 27, 2017	Dec. 28, 2016	Dec. 30, 2015	Dec. 31, 2014
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 10,114	$ 15,568	$ 23,155	$ 0	$ 0
Charged to costs and expenses	782	0	90	0	0
Charged to other accounts	0	3,455	1,965	39,700	0
Reductions	(3,971)	(8,909)	9,642	16,545	0
Balance at end of period	6,925	$ 10,114	$ 15,568	$ 23,155	$ 0
Reductions related to revaluation of tax reform	$ (4,780)

Valuation Allowances and Reserves, Deductions Related to Revaluation Adjustment of Tax Cuts and Jobs Act

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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

+ References

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- Definition

Amount of decrease in valuation and qualifying accounts and reserves.

+ References

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