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Pension And Other Postretirement Benefits (Narrative) (Details) - USD ($) $ in Millions | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2022 | Dec. 31, 2021
Pension Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Employer contributions | $ 1.3 |
Defined Benefit Plan, Pension Asset, (Increase)Decrease For Remeasurement Due To Settlement | 39.8 |
Change in Regulatory Assets Due to Interim Measurement | 30.0 |
Change in Accumulated Other Comprehensive Income Due to Interim Measurement | 3.5 |
Change to Defined Benefit Plan Net Periodic Costs Due to Interim Measurement | $ 5.7 |
Discount rate | 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%
Other Postretirement Benefit Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Employer contributions | $ 10.5 |

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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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