Financial Instruments Measured at Fair Value - Additional Information (Detail) (USD $)	3 Months Ended	6 Months Ended
	Jun. 29, 2013	Jun. 29, 2013	Jun. 29, 2013 Variable rate demand notes [Member]	Dec. 29, 2012 Variable rate demand notes [Member]
Investment [Line Items]
Variable rate demand note maturity year	2037	2037
Securities amortized cost, Due in one year or less			$ 1,400,000	$ 1,400,000
Securities fair value, Due in one year or less			1,500,000	1,500,000
Derivative instrument income (loss), current net income	$ 40,000	$ 300,000