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Retirement Benefits (Components Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Non-service Cost or Income Components | $ 247 | $ 304 | $ 295
Pension Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | 82 | 88 | 79
Interest cost | 234 | 222 | 221
Expected return on plan assets(b) | (303) | (327) | (333)
Prior service cost (credit) | 0 | 0 | 0
Actuarial (gain) | (34) | (67) | (115)
Defined Benefit Plan, Non-service Cost or Income Components | (103) | (172) | (227)
Net periodic benefit cost (income)(d) | $ (21) | (84) | (148)
Defined Benefit Plan, Amortization of Gain (Loss) | 10 years |  |
Defined Benefit Plan, Difference Between Actual and Expected Return (Loss) on Plan Assets Amortization Period | 4 years |  |
Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Service cost | $ 10 | 12 | 12
Interest cost | 45 | 44 | 45
Expected return on plan assets(b) | (94) | (93) | (91)
Prior service cost (credit) | (4) | (4) | (4)
Actuarial (gain) | (38) | (38) | (45)
Defined Benefit Plan, Non-service Cost or Income Components | (91) | (91) | (95)
Net periodic benefit cost (income)(d) | $ (81) | $ (79) | $ (83)
Defined Benefit Plan, Amortization of Gain (Loss) | 10 years |  |
Defined Benefit Plan, Difference Between Actual and Expected Return (Loss) on Plan Assets Amortization Period | 4 years |  |

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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. + 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 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. + 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 45 -Paragraph 3A -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480482/715-20-55-18 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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