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Pension And Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Sep. 30, 2022 | Jun. 30, 2022 | Sep. 30, 2021 | Jun. 30, 2022 | Sep. 30, 2022 | Sep. 30, 2021 | Dec. 31, 2021
Pension Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Employer contributions |  |  |  |  | $ 2.1 |  |
Defined Benefit Plan, Pension Asset, (Increase)Decrease For Remeasurement Due To Settlement |  | $ 39.8 |  |  |  |  |
Change in Regulatory Assets Due to Interim Measurement |  | 30.0 |  | $ 30.0 |  |  |
Change in Accumulated Other Comprehensive Income Due to Interim Measurement |  | 3.5 |  | 3.5 |  |  |
Change to Defined Benefit Plan Net Periodic Costs Due to Interim Measurement |  | $ 5.7 |  | $ 5.7 |  |  |
Discount rate |  | 4.13% |  | 4.13% |  |  | 2.60%
Discount rate- service cost |  |  |  | 4.30% |  |  | 2.85%
Discount rate - interest cost |  |  |  | 3.64% |  |  | 1.90%
Expected return on assets |  |  |  | 5.70% |  |  | 4.80%
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement | $ 3.0 | $ 6.3 | $ 2.9 |  | 9.3 | $ 9.5 |
Other Postretirement Benefit Plan |  |  |  |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |
Employer contributions |  |  |  |  | 15.9 |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement | $ 0.0 |  | $ 0.0 |  | $ 0.0 | $ 0.0 |

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(1) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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