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Pension and Other Postretirement Benefits (Schedule Of Changes In The Fair Value Of The Plan Level Three Assets) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | $ 2,422.5 |
Fair value of plan assets at end of year | 2,084.1 | $ 2,422.5
Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | 98.9 | 73.1
Total gains or losses (unrealized / realized) | 2.7 | 2.9
Purchases | 2.5 | 43.1
(Sales) | (18.0) | (20.2)
Fair value of plan assets at end of year | 86.1 | 98.9
Real Estate [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | 49.9 | 9.2
Total gains or losses (unrealized / realized) | 1.7 | (0.6)
Purchases | 1.8 | 42.1
(Sales) | (0.7) | (0.8)
Fair value of plan assets at end of year | 52.7 | 49.9
Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | 26.7 | 34.8
Total gains or losses (unrealized / realized) | 2.4 | 2.1
Purchases | 0.7 | 0.9
(Sales) | (11.3) | (11.1)
Fair value of plan assets at end of year | 18.5 | 26.7
Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | 19.1 | 24.9
Total gains or losses (unrealized / realized) | (0.6) | 1.1
Purchases | 0.0 | 0.1
(Sales) | (6.0) | (7.0)
Fair value of plan assets at end of year | 12.5 | 19.1
Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | 3.2 | 4.1
Total gains or losses (unrealized / realized) | (0.8) | 0.4
Purchases | 0.0 | 0.0
(Sales) | 0.0 | (1.3)
Fair value of plan assets at end of year | 2.4 | 3.2
Fixed Income Securities [Member] | Other Fixed Income [Member] | Significant Unobservable Inputs (Level 3) [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets at beginning of year | $ 0.0 | 0.1
Total gains or losses (unrealized / realized) |  | (0.1)
Purchases |  | 0.0
(Sales) |  | 0.0
Fair value of plan assets at end of year |  | $ 0.0

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