Pension Plans (Summary Of Amounts Included In Accumulated Other Comprehensive Income (Loss)) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Jan. 01, 2011
Pension Plans [Abstract]
Net loss, net of tax	$ (268.0)	$ (206.9)
Prior service cost, net of tax of $1.9 million and $2.0 million, respectively	(3.0)	(3.2)
Amounts included in accumulated other comprehensive income (loss)	(271.0)	(210.1)
Net loss, tax	155.6	122.8
Prior service cost, tax	$ 1.9	$ 2.0

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