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Stock-Based Compensation (Schedule of Valuation Assumptions) (Details)	3 Months Ended		6 Months Ended
	Jul. 01, 2012	Jul. 03, 2011	Jul. 01, 2012	Jul. 03, 2011
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 years 6 months 11 days	4 years 11 months 5 days	6 years 2 months 19 days	4 years 11 months 5 days
Risk-free interest rate	1.16%	1.99%	1.10%	2.00%
Expected volatility	59.03%	58.69%	59.65%	58.50%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 months 2 days	6 months	6 months 2 days	6 months
Risk-free interest rate	0.14%	0.10%	0.14%	0.10%
Expected volatility	67.93%	47.00%	67.93%	47.00%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%

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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