Schedule II-Valuation and Qualifying Accounts (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Allowance for doubtful receivables
Movement in Valuation and Qualifying Accounts
Balance at beginning of period	$ 10,369	$ 7,898	$ 7,555
Charged to profit and loss	1,780	4,674	1,336
Deductions from reserves	(2,227)	(2,203)	(993)
Balance at close of period	9,922	10,369	7,898
Allowance for deferred income tax asset valuation
Movement in Valuation and Qualifying Accounts
Balance at beginning of period	107,767	120,979	123,522
Charged to profit and loss	(3,280)	(13,212)	(2,543)
Balance at close of period	$ 104,487	$ 107,767	$ 120,979

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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

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

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- Definition

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- Definition

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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