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Litigation (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022
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Loss Contingencies [Line Items] |  |  |
Potential liabilities related to litigation and environmental matters | $ 21,000 | $ 31,900 | $ 33,500
Insurance Receivable | 98 | 10,000 | 11,900
Regulatory Assets | $ 20,100 | $ 20,900 | $ 20,500

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