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Other Commitments And Contingencies (Narrative) (Details) $ in Thousands | Mar. 18, 2024 USD ($) | Mar. 31, 2024 USD ($) Rate | Dec. 31, 2023 USD ($)
--- | --- | --- | ---
Other Commitments And Contingencies [Line Items] |  |  |
Guaranty Liabilities |  | $ 672,300 | $ 646,100
Recorded reserves to cover environmental remediation at various sites |  | $ 77,800 | 80,000
Wind Power Purchase Agreement, Purchase Percentage | Rate |  | 100.00% |
Payments to Acquire Assets, Investing Activities | $ 110,600 |  |
MGP Sites |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Number of waste disposal sites identified by program |  | 53 |
Liability for Estimated Remediation Costs |  | $ 72,800 | $ 73,700
Reasonably possible remediation costs variance from reserve |  | 15,100 |
Standby Letters of Credit |  |  |
Other Commitments And Contingencies [Line Items] |  |  |
Long-term Line of Credit |  | $ 9,900 |

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