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v3.24.0.1

Retirement Benefits (Summary of Changes in the Fair Value of the Plans Level 3 Assets) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | $ 13,042 |
Fair value of plan assets at end of year | 13,452 | $ 13,042
Other investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 329 |
Fair value of plan assets at end of year | 323 | 329
Corporate stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 564 |
Fair value of plan assets at end of year | 265 | 564
Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 309 | 663
Purchases | 16 | 18
Sales | (15) | (19)
Unrealized Gain/ (Loss) | (21) | (302)
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 14 | (51)
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | 303 | 309
Significant Unobservable Inputs (Level 3) | Other investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 308 | 662
Purchases | 16 | 18
Sales | (15) | (19)
Unrealized Gain/ (Loss) | (21) | (302)
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 14 | (51)
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | 302 | 308
Significant Unobservable Inputs (Level 3) | Corporate stocks |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value of plan assets at beginning of year | 1 | 1
Purchases | 0 | 0
Sales | 0 | 0
Unrealized Gain/ (Loss) | 0 | 0
Realized Gain/ (Loss) | 0 | 0
Exchange Rate Impact | 0 | 0
Transfers in/(out) and Other | 0 | 0
Fair value of plan assets at end of year | $ 1 | $ 1

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- Definition Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets sold. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 17 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480482/715-20-55-17 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02)(A) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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