Summary of Significant Accounting Policies (Details) (Detail) (USD $)	3 Months Ended	9 Months Ended
	Sep. 24, 2011	Sep. 24, 2011	Sep. 29, 2012	Dec. 31, 2011
Net of allowance for doubtful accounts			$ 200,000	$ 500,000
Issue of shares of common stock excluded from computation	2,085,000	1,897,000
Deferred revenue			2,400,000	6,600,000
Deferred profit			1,802,000	2,821,000	[1]
Accumulated other comprehensive loss			$ (171,000)	$ (12,000)	[1]

[1] Derived from December 31, 2011 audited financial statements.