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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, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Pension Plan |  |  |
Net prior service cost/(credit) | $ 0.2 | $ 0.0 |
Net actuarial (gain)/loss | 158.9 | (26.0) |
Settlements | (12.4) | (11.4) | $ (10.5)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | (0.1) | (0.1) | (0.7)
Less: amortization of net actuarial (gain) loss | (20.3) | (21.7) | (33.8)
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | 126.3 | (59.2) |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | 136.6 | (66.0) |
Other Postretirement Benefits |  |  |
Net prior service cost/(credit) | 2.1 | 0.1 |
Net actuarial (gain)/loss | (21.8) | (23.3) |
Settlements | 0.0 | 0.0 | (1.5)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | 2.2 | 2.2 | 2.1
Less: amortization of net actuarial (gain) loss | (2.6) | (4.6) | $ (4.9)
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | (20.1) | (25.6) |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | $ (17.4) | $ (22.4) |

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