STOCKHOLDERS' EQUITY. (Details) (USD $)	12 Months Ended			0 Months Ended	12 Months Ended			0 Months Ended	12 Months Ended			12 Months Ended						12 Months Ended
	Dec. 29, 2012 item	Dec. 31, 2011	Dec. 28, 2013	May 08, 2013 Class A Common Stock	Dec. 28, 2013 Class A Common Stock	Dec. 29, 2012 Class A Common Stock	Dec. 31, 2011 Class A Common Stock	May 08, 2013 Class B Common Stock	Dec. 28, 2013 Class B Common Stock	Jan. 31, 2001 The 2001 Stock Option Plan Class A Common Stock	Jan. 23, 2004 The 2004 Stock Option Plan Class A Common Stock	Dec. 28, 2013 Stock options	Dec. 29, 2012 Stock options	Dec. 31, 2011 Stock options	Dec. 28, 2013 Stock options Minimum	Dec. 28, 2013 Stock options Maximum	May 23, 2012 Stock options Plan Class A Common Stock	Dec. 28, 2013 Stock options Plan Class A Common Stock Maximum
STOCKHOLDERS' EQUITY.
Preferred stock, authorized shares	1,000,000		1,000,000
Preferred stock, par value (in dollars per share)	$ 1		$ 1
Preferred stock, issued shares	0		0
Conversion ratio of Class B common stock into shares of Class A common stock	1
Percentage of Board of Directors that holders of Class A common stock are entitled to elect	33.00%
Stockholders' equity
Percentage of dividend declared on common stock				5.00%				5.00%
Dividend declared (in dollars per share)	$ 0.00	$ 0.00
Dividend paid (in dollars per share)	$ 0.00	$ 0.00
Number of shares of Class B Common Stock converted into Class A Common Stock									30,834
Restricted Stock, additional disclosure
Shares available for grant										891,990	1,297,440						1,000,000
Expiration period															5 years	7 years
Vesting rights (as a percent)												33.33%
Number of shares that can be granted in any one year																		100,000
Options
Outstanding at the beginning of the period (in shares)												1,007,798	1,214,452	1,264,951
Exercised (in shares)					(95,548)	(58,804)	(26,920)					(115,890)	(61,744)	(34,362)
Expired (in shares)												(272,462)	(13,623)	(7,754)
Forfeited (in shares)												(84,015)	(131,287)	(8,382)
Outstanding at the end of the period (in shares)												535,431	1,007,798	1,214,452
Weighted - Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)												$ 3.74	$ 3.71	$ 3.65
Exercised (in dollars per share)												$ 1.87	$ 1.63	$ 1.41
Expired (in dollars per share)												$ 6.29	$ 5.86	$ 6.80
Forfeited (in dollars per share)												$ 4.29	$ 4.13	$ 1.44
Outstanding at the end of the period (in dollars per share)												$ 2.79	$ 3.74	$ 3.71
Stock-based compensation, additional disclosure
Total intrinsic value of options exercised												$ 306,985	$ 117,975	$ 47,152