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Litigation (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022
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Loss Contingencies [Line Items] |  |  |
Potential liabilities related to litigation and environmental matters | $ 25.4 | $ 32.9 | $ 30.0
Insurance Receivable | 3.3 | 10.4 | 7.1
Regulatory Assets | $ 20.9 | $ 20.9 | $ 20.8

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