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Pension and Other Postretirement Benefits (Schedule Of Changes In The Fair Value Of The Plan Level Three Assets) (Details) - Significant Unobservable Inputs (Level 3) [Member] $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |
Fair value of plan assets at beginning of year | $ 86.1
Fair value of plan assets at end of year | 0.0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Assets Transferred into (out of) Level 3 | (86.1)
Real Estate [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Fair value of plan assets at beginning of year | 52.7
Fair value of plan assets at end of year | 0.0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Assets Transferred into (out of) Level 3 | (52.7)
Private Equity Limited Partnerships [Member] | U.S. Multi-Strategy [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Fair value of plan assets at beginning of year | 18.5
Fair value of plan assets at end of year | 0.0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Assets Transferred into (out of) Level 3 | (18.5)
Private Equity Limited Partnerships [Member] | International Multi-Strategy [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Fair value of plan assets at beginning of year | 12.5
Fair value of plan assets at end of year | 0.0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Assets Transferred into (out of) Level 3 | (12.5)
Private Equity Limited Partnerships [Member] | Distressed Opportunities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Fair value of plan assets at beginning of year | 2.4
Fair value of plan assets at end of year | 0.0
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Assets Transferred into (out of) Level 3 | $ (2.4)

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