Consolidated Balance Sheets (Parenthetical) (unaudited) (USD $)	Jun. 28, 2011	Dec. 28, 2010
Common stock, $.0001 par value per share:
Common stock, par value	$ 0.0001	$ 0.0001
Treasury stock, shares	1,126,398	1,119,092
Class A
Common stock, $.0001 par value per share:
Common stock, shares authorized	112,500,000	112,500,000
Common stock, shares issued	30,149,021	30,125,936
Common stock, shares outstanding	29,022,623	29,006,844
Class B
Common stock, $.0001 par value per share:
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	1,389,087	1,391,607
Common stock, shares outstanding	1,389,087	1,391,607