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v3.25.3

Retirement Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Pension remeasurement gain | $ 0 | $ (23) | $ (44) | $ (25)
Pension building sale - loss | 19 |  | 19 |
OPEB remeasurement (gain) loss | 0 | 21 | 8 | (6)
Pension [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 11 | 11 | 33 | 34
Interest cost on projected benefit obligation | 31 | 31 | 95 | 94
Expected return on plan assets | (38) | (40) | (114) | (124)
Pension remeasurement gain |  | (23) | (44) | (25)
Pension building sale - loss | 19 |  | 19 |
Net periodic pension (benefit) costs | 23 | (21) | (11) | (21)
Pension special termination benefit enhancements |  | 1 |  | 11
Total pension periodic postretirement (benefit) cost | 23 | (20) | (11) | (10)
OPEB [Member] |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 3 | 2 | 5 | 5
Interest cost on projected benefit obligation | 8 | 7 | 22 | 22
Amortization of prior service credit gain recognized | (7) | (6) | (19) | (19)
OPEB remeasurement (gain) loss |  | 21 | 8 | (6)
Total pension periodic postretirement (benefit) cost | $ 4 | $ 24 | $ 16 | $ 2

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- Definition Pension Remeasurement Gain (Loss) + References No definition available. + Details
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- Definition Total Disclosed Benefit Cost, inclusive of all Net Periodic Benefit Cost Components and Settlement Costs, Curtailment Costs, and Special Termination Benefits + References No definition available. + Details
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- Definition Amount of prior service cost (credit) 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)(5) -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)(5) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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