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Pension and Other Postretirement Benefits (Schedule Of Changes In Plan Assets And Projected Benefit Obligations Recognized In Other Comprehensive Income) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Pension Plan |  |  |
Net prior service cost/(credit) | $ 0.0 | $ 0.2 |
Net actuarial (gain)/loss | (20.9) | 158.9 |
Settlements | (9.2) | (12.4) | $ (11.4)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | (0.1) | (0.1) | (0.1)
Less: amortization of net actuarial (gain) loss | (33.7) | (20.3) | (21.7)
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | (63.9) | 126.3 |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | (26.5) | 136.6 |
Other Postretirement Benefits |  |  |
Net prior service cost/(credit) | 3.3 | 2.1 |
Net actuarial (gain)/loss | 16.0 | (21.8) |
Settlements | 0.0 | 0.0 | 0.0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | 2.1 | 2.2 | 2.2
Less: amortization of net actuarial (gain) loss | (3.3) | (2.6) | $ (4.6)
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | 18.1 | (20.1) |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | $ 31.1 | $ (17.4) |

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