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Debt - Additional Information (Detail) - USD ($) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 12, 2024 | Dec. 31, 2024 | Sep. 11, 2024 | Dec. 31, 2023
Debt Instrument [Line Items] |  |  |  |
Funds available under revolving credit facility |  | $ 1,500,000,000 |  |
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration] | Canadian Dollar Offered Rate C D O R [Member] |  |  |
Variable rate | 1.25% |  |  |
Capitalization ratio, Maximum | 60.00% |  |  |
Capitalization ratio, Actual |  | 23.80% |  |
Other debt |  | $ 153,000,000 |  | $ 139,000,000
First payment |  | 37,000,000 |  |
Outstanding letters of credit under various bilateral letter of credit facilities |  | 500,000,000 |  |
Carrying value of Unsecured Senior Notes |  | 1,587,000,000 |  | 1,586,000,000
Unsecured Debt [Member] | Fair Value, Inputs, Level 2 [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Fair value of Unsecured Senior Notes |  | 1,285,000,000 |  | $ 1,316,000,000
Noncontrolling Interests [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Other debt |  | 58,000,000 |  |
Other debt due in next twelve months |  | 27,000,000 |  |
Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Credit facility, extendable borrowing capacity | $ 2,500,000,000 |  |  |
Line of credit facility current borrowing capacity |  |  | $ 2,000,000,000 |
Variable rate basis | Secured Overnight Financing Rate (SOFR), Euro Interbank Offered Rate (EURIBOR), Sterling Overnight Index Average (SONIA), Canadian Overnight Repo Rate Average (CORRA), or Norwegian Interbank Offered Rate (NIBOR), |  |  |
Outstanding letters of credit issued |  | 0 |  |
Foreign Line of Credit [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Line of credit facility current borrowing capacity |  | $ 150,000,000 |  |
Variable rate |  | 1.40% |  |
Additional line of credit facility borrowing capacity |  | $ 120,000,000 |  |
Debt to equity ratio maximum |  | 75.00% |  |
Borrowings |  | $ 94,000,000 |  |
First payment |  | $ 11,000,000 |  |
Line of credit repayments beginning date |  | 2022-12 |  |
Line of credit repayments ending date |  | 2032-06 |  |
Unsecured Revolving Credit Facility [Member] |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Debt instrument, term | 5 years |  |  |
Line of credit facility current borrowing capacity | $ 1,500,000,000 |  |  |

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- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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