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Stock-Based Compensation (Assumption And Weighted-Average Fair Values Used In The Black Scholes Model) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 25, 2012
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Weighted-average fair value of grants	$ 5.42	$ 5.39
Expected dividend yield	0.00%	0.00%
Expected volatility	50.85%	51.83%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years 0 months 26 days	5 years 0 months 22 days
Risk-free interest rate	0.792%	0.893%

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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