Debt Tender Offer, Interest Rate, Stated Percentage

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- Definition

Line of Credit Facility, Increase in Borrowing Capacity

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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- Definition

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

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Fair value amount of debt instrument that was repurchased.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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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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Long-term Debt and Finance Leases - Narrative (Details) - USD ($)				1 Months Ended		3 Months Ended		6 Months Ended
	Jun. 30, 2026	May 14, 2026	Jan. 30, 2026	Feb. 28, 2026	Jan. 31, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Jul. 31, 2026	Apr. 28, 2026	Apr. 14, 2026
Debt Instrument [Line Items]
Loss on debt extinguishment						$ 9,000,000	$ 10,000,000	$ 9,000,000	$ 10,000,000
Revolving Credit Facility \| Incremental Term Loan B Facility
Debt Instrument [Line Items]
Debt issuance amount											$ 900,000,000
Revolving Credit Facility \| Recourse Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Basis spread on variable rate								1.72%
Senior Unsecured Notes \| Senior Notes
Debt Instrument [Line Items]
Debt issuance amount											2,100,000,000
Senior Notes, due 2034 \| Senior Notes
Debt Instrument [Line Items]
Debt issuance amount											$ 1,050,000,000.00
Interest rate %											5.875%
Senior Notes, due 2034 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate %	5.875%					5.875%		5.875%
Senior Notes, due 2036 \| Senior Notes
Debt Instrument [Line Items]
Debt issuance amount											$ 1,050,000,000.00
Interest rate %											6.125%
Senior Notes, due 2036 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate %	6.125%					6.125%		6.125%
Senior Secured First Lien Notes, due 2031 \| Senior Notes
Debt Instrument [Line Items]
Debt issuance amount											$ 500,000,000
Interest rate %											4.955%
Senior Secured First Lien Notes, due 2031 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate %	4.955%					4.955%		4.955%
Bilateral Letter of Credit Facilities \| Secured Debt \| Letter of Credit
Debt Instrument [Line Items]
Increase to existing revolving commitments				$ 90,000,000	$ 410,000,000
Letters of credit issued	$ 784,000,000					$ 784,000,000		$ 784,000,000
Credit Default Swap Facility \| Secured Debt \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit issued	0					0		0
Revolving credit commitments	$ 250,000,000					$ 250,000,000		$ 250,000,000
3.000% Cedar Bayou 5 TEF Loan Due 2045 \| Recourse Debt \| Subsequent Event
Debt Instrument [Line Items]
Borrowings										$ 344,000,000
Greens Bayou 6 TEF loan, due 2045 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate %	3.00%					3.00%		3.00%
Greens Bayou 6 TEF loan, due 2045 \| Recourse Debt \| Subsequent Event
Debt Instrument [Line Items]
Borrowings										$ 167,000,000
Receivables Facility, due 2027 \| Secured Debt \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit issued	$ 991,000,000					$ 991,000,000		$ 991,000,000
Lightning Senior Secured Notes, due 2032
Debt Instrument [Line Items]
Debt issuance amount												$ 1,495,000,000
Tender offer interest rate, percentage												99.67%
Debt repurchased amount												$ 1,600,000,000
Aggregate principal redeemed		$ 5,000,000
Debt redemption price, percentage		101.375%
Loss on debt extinguishment		$ 9,000,000
Lightning Senior Secured Notes, due 2032 \| LS Power Portfolio
Debt Instrument [Line Items]
Debt issuance amount			$ 3,200,000,000
Interest rate %			7.25%
Lightning Senior Secured Notes, due 2032 \| Senior Notes \| LS Power Portfolio
Debt Instrument [Line Items]
Debt issuance amount			$ 1,500,000,000
Interest rate %			7.25%
Lightning Senior Secured Notes, due 2032 \| Non Recourse Debt \| LS Power Portfolio
Debt Instrument [Line Items]
Interest rate %	7.25%		7.25%			7.25%		7.25%
Lightning Credit Agreement \| Revolving Credit Facility \| LS Power Portfolio
Debt Instrument [Line Items]
Letters of credit issued	$ 82,000,000					$ 82,000,000		$ 82,000,000
Revolving credit commitments			$ 600,000,000
Borrowings	$ 0					$ 0		$ 0
Basis spread on variable rate	1.75%		2.00%
Lightning Credit Agreement \| Lightning Term Loan, due 2031 \| LS Power Portfolio
Debt Instrument [Line Items]
Debt issuance amount			$ 1,750,000,000
Basis spread on variable rate	2.00%		2.25%