Long-term Debt and Line of Credit (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011
Debt Instrument [Line Items]
Line of credit, current borrowing capacity	$ 50.0
Line of credit, expiration date	2015-03-31
Basis spread on variable rate	0.45%
Commitment fee	0.15%
Debt, covenant compliance	The Company was in compliance with all covenants as of December 31, 2011 and December 25, 2010.
Alternative Prime Rate
Debt Instrument [Line Items]
Debt interest rate at end of period	3.25%
LIBOR rate
Debt Instrument [Line Items]
Debt interest rate at end of period	0.28%