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Stock-Based Compensation (Schedule of Valuation Assumptions) (Details)	3 Months Ended			9 Months Ended
	Sep. 29, 2013	Sep. 30, 2012	Apr. 01, 2012	Sep. 29, 2013	Sep. 30, 2012
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	4 years 11 months 1 day	4 years 11 months 1 day		6 years 0 months 29 days	5 years 6 months 29 days
Risk-free interest rate	1.51%	0.67%		1.19%	0.89%
Expected volatility	62.62%	65.56%		60.53%	62.59%
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 2 days		6 months 2 days	6 months 2 days
Risk-free interest rate	0.09%	0.14%	0.14%	0.09%
Expected volatility	39.03%	67.93%	67.93%	39.03%
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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