Long-Term Debt and Other Credit Facilities - Schedule of Line of Credit Facilities (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Committed Capacity	$ 1,245
Unused Capacity	916
Line of Credit \| RCF
Debt Instrument [Line Items]
Committed Capacity	700
Unused Capacity	700
Line of Credit \| TLC
Debt Instrument [Line Items]
Committed Capacity	470
Unused Capacity	159
Line of Credit \| Bilateral LCF
Debt Instrument [Line Items]
Committed Capacity	75
Unused Capacity	57
Letter of Credit \| RCF
Debt Instrument [Line Items]
Committed Capacity	475
Revolving Credit Facility
Debt Instrument [Line Items]
LCs Issued	0	$ 0
Revolving Credit Facility \| Line of Credit \| RCF
Debt Instrument [Line Items]
LCs Issued	0	0
Letter of Credit
Debt Instrument [Line Items]
LCs Issued	329	540
Letter of Credit \| Line of Credit \| RCF
Debt Instrument [Line Items]
LCs Issued	0	62
Letter of Credit \| Line of Credit \| TLC
Debt Instrument [Line Items]
LCs Issued	311	404
Collateral amount	472	472
Letter of Credit \| Line of Credit \| Bilateral LCF
Debt Instrument [Line Items]
LCs Issued	$ 18	$ 74

Amount of assets pledged to secure a debt instrument.

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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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