The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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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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COMMITMENTS AND CONTINGENCIES - Guarantees and Obligations Narrative (Details) - USD ($)	Dec. 31, 2025	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jul. 09, 2024	Feb. 13, 2024
Loss Contingencies [Line Items]
Fair value of guarantees	$ 1,300,000		$ 1,200,000
Maximum exposure				$ 850,000,000
Letter of Credit \| Eversource
Loss Contingencies [Line Items]
Amount of long-term debt requested for issuance	25,000,000
Borrowings outstanding	$ 0
South Fork Wind And Revolution Wind
Loss Contingencies [Line Items]
Ownership interest (in percent)		50.00%				50.00%
Sunrise Wind, LLC
Loss Contingencies [Line Items]
Ownership interest (in percent)					50.00%