Capped Call, Convertible Debt, Conversion, Premium

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Debt Instrument, Amortization Rate

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- Definition

Line of Credit Facility, Maximum Borrowing Capacity, Increase

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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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

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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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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Percentage of principal amount of debt redeemed.

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Face (par) amount of the original 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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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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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Long-term Debt and Finance Leases - Narrative (Details) - USD ($) $ in Millions						1 Months Ended	3 Months Ended			9 Months Ended
	Oct. 08, 2025	Jul. 22, 2025	Jul. 11, 2025	Jul. 08, 2025	May 27, 2025	Oct. 31, 2025	Oct. 31, 2025	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Oct. 23, 2025	Sep. 26, 2025	Jul. 31, 2025	May 12, 2025	Dec. 31, 2024	Jun. 30, 2024
Debt Instrument [Line Items]
Loss on debt extinguishment								$ 0	$ 0	$ 10	$ 260
Capped call, convertible debt, conversion, premium				$ 257
Senior Notes \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, aggregate principal	$ 3,650
Senior Notes \| Subsequent Event \| Senior Lien
Debt Instrument [Line Items]
Debt instrument, aggregate principal	1,250
Recourse Debt
Debt Instrument [Line Items]
Borrowings outstanding								$ 12,025		$ 12,025						$ 10,892
New Senior Notes Due 2034 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, aggregate principal	$ 1,250
Interest rate	5.75%
New Senior Notes Due 2036 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, aggregate principal	$ 2,400
Interest rate	6.00%
Senior Secured Notes Due 2030 \| Subsequent Event
Debt Instrument [Line Items]
Debt redemption price, percentage	101.00%
Senior Secured Notes Due 2030 \| Subsequent Event \| Senior Lien
Debt Instrument [Line Items]
Debt instrument, aggregate principal	$ 625
Interest rate	4.734%
Senior Secured Notes Due 2035 \| Subsequent Event \| Senior Lien
Debt Instrument [Line Items]
Debt instrument, aggregate principal	$ 625
Interest rate	5.407%
Senior Secured First Lien Notes, due 2025 \| Subsequent Event
Debt Instrument [Line Items]
Interest rate	2.00%
Aggregate principal redeemed	$ 500
Senior Secured First Lien Notes, due 2025 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate								2.00%		2.00%
Borrowings outstanding								$ 500		$ 500						500
New Unsecured Notes \| Subsequent Event
Debt Instrument [Line Items]
Debt redemption price, percentage	100.00%
Senior Secured Bridge Facility \| Bridge Loan
Debt Instrument [Line Items]
Revolving credit commitments															$ 4,400
Credit Agreement \| Term Loan \| Incremental Term Loan B Facility
Debt Instrument [Line Items]
Revolving credit commitments		$ 1,000
Basis spread on variable rate		1.00%
Amortization rate			1.00%
Credit Agreement \| Term Loan \| Incremental Term Loan B Facility \| Fed Funds Rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.50%
Credit Agreement \| Term Loan \| Incremental Term Loan B Facility \| SOFR
Debt Instrument [Line Items]
Basis spread on variable rate		0.00%
Credit Agreement \| Term Loan \| Incremental Term Loan B Facility \| SOFR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		0.75%
Credit Agreement \| Term Loan \| Incremental Term Loan B Facility \| SOFR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
Credit Agreement \| Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit commitments					$ 4,600
Increase revolving commitments					$ 390
Convertible Senior Notes, due 2048
Debt Instrument [Line Items]
Aggregate principal redeemed				$ 12					343		343
Redemption price, percentage				100.00%
Cash paid				$ 220							603
Loss on debt extinguishment											260
Debt conversion, shares issued (in shares)				3,986,335
Convertible Senior Notes, due 2048 \| Senior Notes
Debt Instrument [Line Items]
Capped call, convertible debt, conversion, premium																	$ 257
Borrowings outstanding																	$ 232
Convertible Senior Notes, due 2048 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate								2.75%		2.75%
Capped call, convertible debt, conversion, premium									257		257
Borrowings outstanding								$ 0	$ 232	$ 0	$ 232					232
T.H. Wharton TEF loan, due 2045 \| Public Utility Commission of Texas
Debt Instrument [Line Items]
Debt instrument, aggregate principal														$ 216
Interest rate														3.00%
T.H. Wharton TEF loan, due 2045 \| Subsequent Event \| Public Utility Commission of Texas
Debt Instrument [Line Items]
Disbursements from loan							$ 178
T.H. Wharton TEF loan, due 2045 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate								3.00%		3.00%
Borrowings outstanding								$ 177		$ 177						0
Cedar Bayou 5 TEF loan, due 2045 \| Public Utility Commission of Texas
Debt Instrument [Line Items]
Debt instrument, aggregate principal													$ 562
Interest rate													3.00%
Cedar Bayou 5 TEF loan, due 2045 \| Subsequent Event \| Public Utility Commission of Texas
Debt Instrument [Line Items]
Disbursements from loan						$ 230
Cedar Bayou 5 TEF loan, due 2045 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate								3.00%		3.00%
Borrowings outstanding								$ 200		$ 200						$ 0
Indian River Power2020 Tax Exempt Bonds Due 2040 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, aggregate principal												$ 57
Interest rate												4.00%
Indian River Power 2020 Tax Exempt Bonds Due 2045 \| Subsequent Event
Debt Instrument [Line Items]
Debt instrument, aggregate principal												$ 190
Interest rate												4.00%