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Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Mar. 27, 2015	Mar. 28, 2014	Dec. 26, 2014	Dec. 27, 2013
Income Taxes [Line Items]
Income tax provision	$ 519,000us-gaap_IncomeTaxExpenseBenefit	$ 1,476,000us-gaap_IncomeTaxExpenseBenefit
Effective tax rate	30.70%	17.30%
Undistributed earnings of foreign subsidiaries	64,000,000
Gross liability for unrecognized tax benefits	374,000us-gaap_UnrecognizedTaxBenefits	175,000us-gaap_UnrecognizedTaxBenefits	356,000us-gaap_UnrecognizedTaxBenefits	165,000us-gaap_UnrecognizedTaxBenefits
Income tax holiday, description	The Company is currently enjoying a zero rate tax holiday related to its Singapore subsidiary that will expire for tax years beginning January 2016.
Income tax holiday, amount	0
Singapore [Member]
Income Taxes [Line Items]
Net profit	$ 2,500,000