CAPITALIZATION - Long-term Debt and Other Long-term Obligations (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Schedule of Capitalization [Line Items]
Finance lease obligations	$ 14	$ 23
Unamortized debt discounts	(9)	(5)
Unamortized debt issuance costs	(127)	(110)
Unamortized fair value adjustments	3	5
Currently payable long-term debt	(1,250)	(351)
Total long-term debt and other long-term obligations	22,885	21,203
FMBs and secured notes - fixed rate
Schedule of Capitalization [Line Items]
FMBs and secured notes - fixed rate	$ 5,709	5,153
FMBs and secured notes - fixed rate \| Minimum
Schedule of Capitalization [Line Items]
Interest rate (percent)	2.65%
FMBs and secured notes - fixed rate \| Maximum
Schedule of Capitalization [Line Items]
Interest rate (percent)	8.25%
Unsecured notes - fixed rate
Schedule of Capitalization [Line Items]
Unsecured notes - fixed rate	$ 18,545	$ 16,488
Unsecured notes - fixed rate \| Minimum
Schedule of Capitalization [Line Items]
Interest rate (percent)	1.60%
Unsecured notes - fixed rate \| Maximum
Schedule of Capitalization [Line Items]
Interest rate (percent)	7.375%

Debt Instrument, Unamortized Merger Fair Value Adjustments

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

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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- Definition

Amount of long-term debt and lease obligation, classified as noncurrent.

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt classified as current. Excludes lease obligation.

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Amount of long-term debt classified as other.

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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

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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