Schedule for Gross Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 27, 2014	Dec. 28, 2013
Income Tax Disclosure [Line Items]
Gross unrecognized tax benefits - beginning of the year	$ 2,261us-gaap_UnrecognizedTaxBenefits	$ 2,329us-gaap_UnrecognizedTaxBenefits
Gross increases related to current year tax positions	373	303
Gross increases related to prior year tax positions	310	111
Gross decreases related to prior year tax positions	(109)	(104)
Settlements	(34)	(72)
Lapse of statute of limitations	(181)	(306)
Gross unrecognized tax benefits - end of the year	$ 2,620us-gaap_UnrecognizedTaxBenefits	$ 2,261us-gaap_UnrecognizedTaxBenefits

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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