Stock-Based Compensation (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Oct. 01, 2011	Oct. 02, 2010	Oct. 01, 2011	Oct. 02, 2010
Stock options exercise prices as percentage of the market value on the date of the grant			100.00%
Compensation expense for stock options	$ 1.9	$ 0.3	$ 9.3	$ 0.4
Proceeds from stock options exercised	3.8		7.0
Unrecognized compensation expense related to unvested restricted stock	2.4		2.4
Weighted average recognition period for unrecognized compensation expense related to unvested restricted stock (years)			1.5
Stock Options Granted Prior To 2006 [Member]
Stock options vesting period			six months
Stock options term, years			7
Stock Options Granted In 2010 And 2011 [Member]
Stock options vesting period			three years
Stock options term, years			10
RSU [Member]
Share-based compensation expense	6.5	7.6	26.2	30.1
Unrecognized compensation expense related to unvested restricted stock	29.1		29.1
Weighted average recognition period for unrecognized compensation expense related to unvested restricted stock (years)			1.7
RSA [Member]
Additional common stock units for election of deferred annual incentive award, percentage			25.00%
Compensation expense for stock options	0.4	1.0	4.7	3.5
Unrecognized compensation expense related to unvested restricted stock	$ 1.1		$ 1.1
Weighted average recognition period for unrecognized compensation expense related to unvested restricted stock (years)			1.5

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Stock Option Exercise Price As Percentage Of Market Value

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The period in which a stock option can be exercised.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

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Description of the period of time over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, which may be expressed in a variety of ways (for example, in years, month and year).

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Equity-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

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The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

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