Variable Interest Entity, Maximum Capacity

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

The proceeds from the sale of an interest in a unit of partnership.

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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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- 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

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Variable Interest Entities (Narrative) (Details) $ in Millions	1 Months Ended	6 Months Ended
	Mar. 31, 2025 USD ($) MW	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Variable Interest Entity [Line Items]
Proceeds from the sale of membership interests in VIEs		$ 44	$ 0
Securitization bonds
Variable Interest Entity [Line Items]
Total principal amount outstanding		643		$ 700
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Regulatory asset		609		666
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Investments		$ 57		$ 64
Variable Interest Entity, Not Primary Beneficiary \| T.E.S. Filer City
Variable Interest Entity [Line Items]
Ownership interest		50.00%
Variable Interest Entity, Not Primary Beneficiary \| Grayling
Variable Interest Entity [Line Items]
Ownership interest		50.00%
Variable Interest Entity, Not Primary Beneficiary \| Genesee
Variable Interest Entity [Line Items]
Ownership interest		50.00%
Variable Interest Entity, Not Primary Beneficiary \| Craven
Variable Interest Entity [Line Items]
Ownership interest		50.00%
NWO Wind Equity Holdings
Variable Interest Entity [Line Items]
Proceeds from the sale of membership interests in VIEs	$ 36
NWO Wind Equity Holdings \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Ownership interest	50.00%
NWO Holdco \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Nameplate capacity (in MW) \| MW	100
Delta Township, Michigan, Solar Project
Variable Interest Entity [Line Items]
Proceeds from the sale of membership interests in VIEs	$ 8
Delta Township, Michigan, Solar Project \| Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Ownership interest	50.00%
Nameplate capacity (in MW) \| MW	24