Common Stock Plans (Stock Options, Valuation Assumptions) (Details) (Stock Incentive Plan, Stock options, USD $)	0 Months Ended	12 Months Ended
Jan. 26, 2011 year	Jan. 27, 2010 year	Aug. 24, 2009 year	Jan. 28, 2009 year	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Stock Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Awards granted	293,978	281,110	4,750	538,492	293,978	281,110	543,242
Fair market value of stock at grant	$ 19.65	$ 16.47	$ 15.00	$ 8.83
Expected life of award	5.8	5.7	5.7	5.7
Risk-free interest rate	2.45%	2.76%	2.80%	1.89%
Annualized volatility rate	37.80%	37.30%	36.90%	34.80%
Dividend yield	1.00%	1.10%	1.20%	1.70%

The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

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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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