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Stock-Based Compensation Weighted Average Assumptions (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	8 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life (in years)	8 years	8 years 1 month 6 days	7 years 6 months	8 years 3 months 18 days
Risk-free interest rate	1.70%	3.10%	1.40%	3.20%
Volatility factor	49.00%	48.00%	48.00%	48.00%
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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