Pension And Postretirement Benefits (Schedule Of Fair Value Of Company Pension Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	$ 965.8	$ 877.2
Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	373.9	322.8
Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	15.2	13.5
Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	22.6	20.8
Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	554.1	520.1
Cash and Money Markets [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	14.7	72.0
Cash and Money Markets [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	14.7	72.0
Cash and Money Markets [Member] | Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0	0.0
Cash and Money Markets [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0	0.0
Common Stocks Actively Managed U.S. Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	130.6	110.7
Common Stocks Actively Managed U.S. Equities [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	130.6	110.7
Common Stocks Actively Managed U.S. Equities [Member] | Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0	0.0
Fixed Income Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.1	0.1
Fixed Income Investments [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0	0.0
Fixed Income Investments [Member] | Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.1	0.1
U.S. Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	77.9	49.4
U.S. Equity Funds [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	77.9	49.4
U.S. Equity Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0	0.0
Non-U.S. Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	203.4	155.2
Non-U.S. Equity Funds [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	44.8	14.4
Non-U.S. Equity Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	158.6	140.8
U.S. Fixed Income, Government and Corporate [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	75.7	59.5
U.S. Fixed Income, Government and Corporate [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	75.7	59.5
registered investment company [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	30.2	16.8
registered investment company [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	30.2	16.8
Non-U.S. Fixed Income, Government And Corporate [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	176.1	155.5
Non-U.S. Fixed Income, Government And Corporate [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	176.1	155.5
International Balanced Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	1.8	1.5
International Balanced Funds [Member] | Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value		0.0
International Balanced Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	1.8	1.5
CollectiveTrust [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	43.8	39.8
CollectiveTrust [Member] | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	22.6	20.8
CollectiveTrust [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	21.2	19.0
Hedge Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	147.3	157.0
Hedge Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	147.3	157.0
International Property Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	49.1	46.3
International Property Funds [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0
International Property Funds [Member] | Fair Value Measured at Net Asset Value Per Share [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	49.1	46.3
Annuity Contract [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	15.1	13.4
Annuity Contract [Member] | Quoted Prices In Active Markets For Identical Assets Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	0.0
Annuity Contract [Member] | Significant Other Observable Inputs Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Total Fair Value	$ 15.1	$ 13.4