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Employee Benefit Plans - Additional Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Pension and Other Postretirement Benefits Disclosure |  |  |
Settlement Loss on the U.S. Pension Plan Annuity Purchase | $ (103.8) | $ 0.0 | $ 0.0
Health Care Cost Trend Rate Assumed for Next Fiscal Year | 7.50% | 7.00% |
Ultimate Health Care Cost Trend Rate | 5.00% |  |
Defined Benefit Plan, Year Health Care Cost Trend Rate Reaches Ultimate Trend Rate | 2036 |  |
Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Payment for Settlement | $ 367.2 | $ 0.0 |
Settlement Loss on the U.S. Pension Plan Annuity Purchase | $ (103.8) | 0.0 | 0.0
Average Remaining Life Expectancy of Plan Participants | 24 years |  |
Alternative Investments, Unfunded Commitments | $ 14.8 | 15.2 |
Pension Plan | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Payment for Settlement | 0.0 | 0.0 |
Settlement Loss on the U.S. Pension Plan Annuity Purchase | $ 0.0 | 0.0 | 0.0
Average Remaining Life Expectancy of Plan Participants | 27 years |  |
Alternative Investments, Unfunded Commitments | $ 2.5 | 7.1 |
Other Postretirement Benefit Plans |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Payment for Settlement | 0.0 | 0.0 |
Settlement Loss on the U.S. Pension Plan Annuity Purchase | $ 0.0 | 0.0 | 0.0
Average Remaining Life Expectancy of Plan Participants | 12 years |  |
Investment Level 3 Transfers Into | $ 0.0 | 0.0 |
Investment Level 3 Transfers Out of | $ 0.0 | $ 0.0 |
Interest Rate During Period | 4.96% | 5.01% |
Other Postretirement Benefit Plans | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Matching Contribution Percent of Employees' Gross Pay | 5.00% |  |
Employer Discretionary Contribution Percentage of earnings | 4.50% |  |
Cost Recognized | $ 83.2 | $ 81.6 | 74.3
Other Postretirement Benefit Plans | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Contribution Plan, Minimum Employee Contribution Eligible for Matching | 1.00% |  |
Defined Contribution Plan, Maximum Employee Contribution Eligible for Matching | 5.00% |  |
Cost Recognized | $ 7.3 | $ 6.6 | $ 5.7
Equity Funds | Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 38.00% |  |
Fixed Maturity Securities | Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 30.00% |  |
All Other Asset Categories | Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 32.00% |  |
Diversified Growth Assets | Pension Plan | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 43.00% |  |
Alternative Investments | Pension Plan | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 20.00% |  |
Liability Driven Investments | Pension Plan | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 37.00% |  |
Minimum | Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Private Equity Partnership Future Liquidation Term | 5 years |  |
Minimum | Other Postretirement Benefit Plans | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Matching Contribution Percent of Employees' Gross Pay | 8.00% |  |
Maximum | Pension Plan | UNITED STATES |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Private Equity Partnership Future Liquidation Term | 8 years |  |
Maximum | Other Postretirement Benefit Plans | Foreign Plan |  |  |
Pension and Other Postretirement Benefits Disclosure |  |  |
Matching Contribution Percent of Employees' Gross Pay | 12.00% |  |

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- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (l) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one 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 50 -Paragraph 1 -Subparagraph (d)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480535/715-20-45-3A Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (h)(7) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a)(7) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-6 + Details
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- Definition Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(8) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
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