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Long-term and Short-term Debt Long-term and Short-term Debt (Narrative - Line of Credit) (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 01, 2037
Committed Credit Facility Six [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | $ 397 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 2,896 |  |  |
Line of Credit Facility, Current Borrowing Capacity | 2,900 |  |  |
General Credit Facility Three [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | 2,703 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 3,000 |  |  |
Committed Credit Facility Three [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | 0 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 350 |  |  |
Committed Credit Facility [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Remaining Borrowing Capacity | 397 |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 3,246 |  |  |
Committed Credit Facility [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | 3,200 |  |  |
Line of Credit Facility, Commitment Fee Amount | 9 | $ 9 | $ 12 |
General Credit Facility [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Commitment Fee Amount | $ 6 | $ 8 | $ 10 |
Forecast [Member] | Committed Credit Facility Six [Member] |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity |  |  |  | $ 2,000

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- Definition Amount of the fee for available but unused credit capacity under the credit facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-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 -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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