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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
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Pension Plan |  |  |
Net prior service cost/(credit) | $ 0.0 | $ 0.0 |
Net actuarial (gain)/loss | (26.0) | (78.2) |
Settlements | (11.4) | (10.5) | $ (9.5)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | (0.1) | (0.7) | (0.2)
Less: amortization of net actuarial (gain) loss | (21.7) | (33.8) | (45.2)
Less: gain attributable to spinoff to Eversource | 0.0 | (33.1) |
Less: prior service cost attributable to spinoff to Eversource | 0.0 | (2.0) |
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | (59.2) | (158.3) |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | (66.0) | (141.3) |
Other Postretirement Benefits |  |  |
Net prior service cost/(credit) | 0.1 | 0.0 |
Net actuarial (gain)/loss | (23.3) | 2.9 |
Settlements | 0.0 | (1.5) | 0.0
Defined Benefit Plan, Amortization of Prior Service Cost (Credit) | 2.2 | 2.1 | 3.2
Less: amortization of net actuarial (gain) loss | (4.6) | (4.9) | $ (2.0)
Less: gain attributable to spinoff to Eversource | 0.0 | 0.0 |
Less: prior service cost attributable to spinoff to Eversource | 0.0 | 0.0 |
Total Recognized in Other Comprehensive Income or Regulatory Asset or Liability | (25.6) | (1.4) |
Amount Recognized in Net Periodic Benefits Cost and Other Comprehensive Income or Regulatory Asset or Liability | $ (22.4) | $ 10.5 |

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