Retirement and Post Retirement Health Care Plans (Schedule Of Fair Value Of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 160.3	$ 162.1
Investments measured at net asset value	51.5	50.2
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	98.8	103.8
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	10.0	8.1	$ 6.2
Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		4.5
Cash And Cash Equivalents [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3.5	4.5
Cash And Cash Equivalents [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Cash And Cash Equivalents [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Domestic Equities [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		24.9
Domestic Equities [Member] | Common Stock [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	22.9	24.9
Domestic Equities [Member] | Common Stock [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Domestic Equities [Member] | Common Stock [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
International Equities [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		9.6
International Equities [Member] | Common Stock [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	12.6	9.6
International Equities [Member] | Common Stock [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
International Equities [Member] | Common Stock [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Fixed Income | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		15.0
Fixed Income | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	15.1	15.0
Fixed Income | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0
Fixed Income | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0
U.S. Equity Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		22.3
U.S. Equity Funds [Member] | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	18.8	22.3
U.S. Equity Funds [Member] | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
U.S. Equity Funds [Member] | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Balanced Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		9.7
Balanced Funds [Member] | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	8.4	9.7
Balanced Funds [Member] | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Balanced Funds [Member] | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0
International Equity Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		16.8
International Equity Funds [Member] | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	16.2	16.8
International Equity Funds [Member] | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
International Equity Funds [Member] | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Other Plan Asset Category [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		1.0
Other Plan Asset Category [Member] | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1.3	1.0
Other Plan Asset Category [Member] | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Other Plan Asset Category [Member] | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Real Estate Investment [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets		8.1
Real Estate Investment [Member] | Mutual Funds [Member] | Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Real Estate Investment [Member] | Mutual Funds [Member] | Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	0.0	0.0
Real Estate Investment [Member] | Mutual Funds [Member] | Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	10.0	8.1
Common Collective Trust Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Investments measured at net asset value	45.1	43.8
Global Emerging Markets Fund Limited Partnership [Member]
Defined Benefit Plan Disclosure [Line Items]
Investments measured at net asset value	6.4	6.4
Estimate of Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	108.8	$ 111.9
Estimate of Fair Value [Member] | Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3.5
Estimate of Fair Value [Member] | Domestic Equities [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	22.9
Estimate of Fair Value [Member] | International Equities [Member] | Common Stock [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	12.6
Estimate of Fair Value [Member] | Fixed Income | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	15.1
Estimate of Fair Value [Member] | U.S. Equity Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	18.8
Estimate of Fair Value [Member] | Balanced Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	8.4
Estimate of Fair Value [Member] | International Equity Funds [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	16.2
Estimate of Fair Value [Member] | Other Plan Asset Category [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	1.3
Estimate of Fair Value [Member] | Real Estate Investment [Member] | Mutual Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 10.0