Pension Benefit Plans (Fair Values Of Pension Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 2,911.1	$ 2,918.5
Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	690.6	629.5
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	592.1	625.4
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Cash and equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23.7	20.1
Cash and equivalents | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23.7	20.1
Common Stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	370.9	273.9
Common Stock | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	347.5	249.4
Common Stock | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23.4	24.5
Preferred stock
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.3	2.6
Preferred stock | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.3	2.6
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	62.9	98.8
Corporate bonds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	62.9	98.8
Government issued
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	82.9	80.5
Government issued | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	82.9	80.5
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	477.7	546.2
Mutual funds | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	315.1	357.4
Mutual funds | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	162.6	188.8
Insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	260.3	232.8
Insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	260.3	232.8
Total plan assets, excluding NAV assets
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1,282.7	1,254.9
NAV assets, mutual funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	289.1	257.6
NAV Assets, insurance contracts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	70.2	70.9
NAV assets, common collective trusts
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	697.8	742.5
NAV assets, venture capital, partnerships and other private investments
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 571.3	$ 592.6