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v3.25.3

Pension Plans, Retirement Benefits and Savings Plans (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Pension Plans [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | $ 28 | $ 29 | $ 85 | $ 87
Interest cost on benefit obligation | 44 | 43 | 132 | 129
Expected return on plan assets | (71) | (74) | (211) | (223)
Net periodic benefit cost (benefit), amortization of unrecognized prior service benefit | 0 | 0 | 0 | 0
Net periodic benefit cost (benefit), amortization of unrecognized net actuarial (gain) loss | 4 | 2 | 11 | 5
Total non-service cost (benefit) | (23) | (29) | (68) | (89)
Net periodic benefit cost (benefit) | 5 | 0 | 17 | (2)
Pension Plans [Member] | Claims and claim adjustment expenses [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | 11 | 11 | 33 | 34
Total non-service cost (benefit) | (9) | (11) | (26) | (34)
Pension Plans [Member] | General and administrative expenses [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | 17 | 18 | 52 | 53
Total non-service cost (benefit) | (14) | (18) | (42) | (55)
Postretirement Benefit Plans [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost on benefit obligation | 1 | 1 | 2 | 3
Expected return on plan assets | 0 | 0 | 0 | 0
Net periodic benefit cost (benefit), amortization of unrecognized prior service benefit | 0 | 0 | (1) | (2)
Net periodic benefit cost (benefit), amortization of unrecognized net actuarial (gain) loss | (3) | (3) | (9) | (7)
Total non-service cost (benefit) | (2) | (2) | (8) | (6)
Net periodic benefit cost (benefit) | (2) | (2) | (8) | (6)
Postretirement Benefit Plans [Member] | Claims and claim adjustment expenses [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | 0 | 0 | 0 | 0
Total non-service cost (benefit) | (1) | 0 | (3) | (2)
Postretirement Benefit Plans [Member] | General and administrative expenses [Member] |  |  |  |
Defined benefit plan disclosure |  |  |  |
Service cost | 0 | 0 | 0 | 0
Total non-service cost (benefit) | $ (1) | $ (2) | $ (5) | $ (4)

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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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- Definition Amount of cost recognized for passage of time related to 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 (a)(2) -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 1 -Subparagraph (h)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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