Fair Value Measurements - Financial Assets Valued on Recurring Basis for Cash and Cash Equivalents and Investments (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 27, 2014		Dec. 28, 2013		Sep. 28, 2013	Dec. 29, 2012
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	$ 1,255		$ 818		$ 1,099	$ 1,030
Short-term investments	39		47
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	1,294		865
Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	1,294		865
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure
Fair Value, Measurements, Recurring | Valuation Techniques | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,255	[1]	818	[1]
Fair Value, Measurements, Recurring | Valuation Techniques | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	39	[2]	47	[2]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 1 | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents	1,255	[1]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 1 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents			818	[1]
Short-term investments	39	[2]	47	[2]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 2 | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		[1]		[1]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 2 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		[2]		[2]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 3 | Cash and cash equivalents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash and cash equivalents		[1]		[1]
Fair Value, Measurements, Recurring | Valuation Techniques | Level 3 | Investments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments		[2]		[2]

[1] Cash equivalents consist primarily of money market funds and short-term investments with original maturity dates of three months or less at the date of purchase, for which the Company determines fair value through quoted market prices.

[2] Investments consist of mutual funds, classified as short-term investments available-for-sale and recorded at fair market value, based on quoted prices of identical assets that are trading in active markets as of the end of the period for which the values are determined. These mutual funds invest in government bonds, stocks and short-term money market funds,