Commitment, Contingencies And Guarantees (Additional Information) (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Loss Contingencies [Line Items]
Accrued liabilities	$ 291.7	$ 293.3
Regulatory assets	432.2	480.1
Environmental
Loss Contingencies [Line Items]
Regulatory assets	10.6	$ 2.9
Manufactured Gas Plant
Loss Contingencies [Line Items]
Insurance Settlements Receivable, Noncurrent	1.5
Site remediation cost	7.4
Accrued liabilities	11.5
Regulatory assets	$ 10.6

Remediation cost

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying amount due after one year of the balance sheet date (or one operating cycle, if longer) of amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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