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OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES - Other Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Provision for Interim Rate Refund	$ 0.0	$ 23.0
Customer Deposits	9.0	7.8
PSAs	5.8	5.9
Other	66.9	81.2
Total Other Current Liabilities	$ 81.7	$ 117.9

X

- Definition

The fair value adjustment for the price of power per MW at market rates compared to those at contract rate at the time of acquisition through the end of the contract term present valued to acquisition date resulting in a current liability.

+ References

No definition available.

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- Definition

Public Utilities Reserve for Interim Rates

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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Amount of liabilities classified as other, due within one year or the normal operating cycle, if longer.

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