XML 54 R42.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Retirement Plans (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2024
Retirement Benefits [Abstract] |
Reconciliation of Balances of Pension Benefit Obligation and Fair Value of Plan Assets | A reconciliation of the beginning and ending balances of the pension benefit obligation and fair value of plan assets and the funded status of the plan is as follows (in millions):
|  | Year Ended December 31, |
|  | 2024 |  |  | 2023 |
Change in pension benefit obligation: |  |  |  |  |  |
Benefit obligation at beginning of year |  | $ | 216.0 |  |  | $ | 211.9 |
Service cost |  |  | 0.6 |  |  |  | 3.3 |
Interest cost |  |  | 9.9 |  |  |  | 10.7 |
Merger of the Buck U.S. pension plan |  |  | 95.4 |  |  |  | — |
Net actuarial loss (gain) |  |  | (10.5 | ) |  |  | 8.8 |
Benefits paid |  |  | (15.4 | ) |  |  | (18.7 | )
Benefit obligation at end of year |  | $ | 296.0 |  |  | $ | 216.0 |
Change in plan assets: |  |  |  |  |  |
Fair value of plan assets at beginning of year |  | $ | 228.9 |  |  | $ | 212.5 |
Actual (loss) return on plan assets |  |  | 15.3 |  |  |  | 35.1 |
Merger of the Buck U.S. pension plan |  |  | 83.7 |  |  |  | — |
Contributions by the Company |  |  | — |  |  |  | — |
Benefits paid |  |  | (15.4 | ) |  |  | (18.7 | )
Fair value of plan assets at end of year |  | $ | 312.5 |  |  | $ | 228.9 |
Funded status of the plan (underfunded) |  | $ | 16.5 |  |  | $ | 12.9 |
Amounts recognized in the consolidated balance sheet consist of: |  |  |  |  |  |
Noncurrent assets - prepaid pension asset |  | $ | 16.5 |  |  | $ | 12.9 |
Accumulated other comprehensive income |  |  | 17.7 |  |  |  | 37.3 |
Net amount included in retained earnings |  | $ | 34.2 |  |  | $ | 50.2 |
Components of Net Periodic Pension Benefit Cost and Other Changes in Plan Assets and Obligations Recognized in Earnings and Other Comprehensive Earnings | The components of the net periodic pension benefit cost for the plan and other changes in plan assets and obligations recognized in earnings and other comprehensive earnings consist of the following (in millions):
|  | Year Ended December 31, |
|  | 2024 |  |  | 2023 |  |  | 2022 |
Net periodic pension cost: |  |  |  |  |  |  |  |  |
Service cost |  | $ | 0.6 |  |  | $ | 3.3 |  |  | $ | 0.5 |
Interest cost on benefit obligation |  |  | 9.9 |  |  |  | 10.7 |  |  |  | 6.8 |
Expected return on plan assets |  |  | (15.4 | ) |  |  | (14.2 | ) |  |  | (19.1 | )
Amortization of net loss |  |  | 2.5 |  |  |  | 4.9 |  |  |  | 2.4 |
Net periodic benefit income (cost) |  |  | (2.4 | ) |  |  | 4.7 |  |  |  | (9.4 | )
Other changes in plan assets and obligations recognized in other comprehensive earnings: |  |  |  |  |  |  |  |  |
Net loss (gain) incurred |  |  | (10.3 | ) |  |  | (12.0 | ) |  |  | 14.1 |
Amortization of net loss |  |  | (2.5 | ) |  |  | (4.9 | ) |  |  | (2.4 | )
Total recognized in other comprehensive income (loss) |  |  | (12.8 | ) |  |  | (16.9 | ) |  |  | 11.7 |
Total recognized in net periodic pension cost and other comprehensive income (loss) |  | $ | (15.2 | ) |  | $ | (12.2 | ) |  | $ | 2.3 |
Weighted Average Assumptions of Pension Benefit Obligation and Net Periodic Pension Benefit Cost | The following weighted average assumptions were used at December 31 in determining the plan’s pension benefit obligation:
|  | December 31, |
|  | 2024 |  |  | 2023 |
Discount rate |  |  | 5.50 | % |  |  | 4.75 | %
Weighted average expected long-term rate of return on plan assets |  |  | 7.00 | % |  |  | 7.00 | %
The following weighted average assumptions were used at January 1 in determining the plan’s net periodic pension benefit cost:
|  | Year Ended December 31, |
|  | 2024 |  |  | 2023 |  |  | 2022 |
Discount rate |  |  | 4.75 | % |  |  | 5.25 | % |  |  | 2.50 | %
Weighted average expected long-term rate of return on plan assets |  |  | 7.00 | % |  |  | 7.00 | % |  |  | 7.00 | %
Schedule of Benefit Payments Expected to be Paid by Plan | The following benefit payments are expected to be paid by the plan (in millions):
2025 |  | $ | 25.2 |
2026 |  |  | 22.1 |
2027 |  |  | 22.5 |
2028 |  |  | 22.5 |
2029 |  |  | 22.6 |
2030 to 2034 |  |  | 448.5 |
Summary of Plans Weighted Average Asset Allocations | The following is a summary of the plan’s weighted average asset at December 31 by asset category:
|  | December 31, |
Asset Category |  | 2024 |  |  | 2023 |
Equity securities |  |  | 0.0 | % |  |  | 61.0 | %
Debt securities |  |  | 100.0 | % |  |  | 32.0 | %
Real estate |  |  | 0.0 | % |  |  | 7.0 | %
Total |  |  | 100.0 | % |  |  | 100.0 | %
Summary of Plan's Assets Carried at Fair Value | The following is a summary of the plan’s assets carried at fair value as of December 31 by level within the fair value hierarchy (in millions):
|  | December 31, |
Fair Value Hierarchy |  | 2024 |  |  | 2023 |
Level 1 |  | $ | — |  |  | $ | — |
Level 2 |  |  | 205.7 |  |  |  | 120.3 |
Level 3 |  |  | 106.8 |  |  |  | 108.6 |
Total fair value |  | $ | 312.5 |  |  | $ | 228.9 |
Reconciliation of Beginning and Ending Balances for Level 3 Assets of Plan Measured at Fair Value | The following is a reconciliation of the beginning and ending balances for the Level 3 assets of the plan measured at fair value (in millions):
|  | Year Ended December 31, |
|  | 2024 |  |  | 2023 |
Fair value at January 1 |  | $ | 108.6 |  |  | $ | 99.6 |
Settlements |  |  | (10.6 | ) |  |  | (1.4 | )
Unrealized gain |  |  | 8.8 |  |  |  | 10.4 |
Fair value at December 31 |  | $ | 106.8 |  |  | $ | 108.6 |

X
- Definition Components of periodic pension benefit cost and other changes in plan assets and obligations recognized in earnings and other comprehensive earnings [Table text block] + References No definition available. + Details
Name: | ajg_ComponentsOfPeriodicPensionBenefitCostAndOtherChangesInPlanAssetsAndObligationsRecognizedInEarningsAndOtherComprehensiveEarningsTableTextBlock
Namespace Prefix: | ajg_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of changes in pension benefit obligations and fair value of plan assets [table text block] + References No definition available. + Details
Name: | ajg_ScheduleOfChangesInPensionBenefitObligationsAndFairValueOfPlanAssetsTableTextBlock
Namespace Prefix: | ajg_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Summary of plans weighted average asset allocations [Table text block] + References No definition available. + Details
Name: | ajg_SummaryOfPlansWeightedAverageAssetAllocationsTableTextBlock
Namespace Prefix: | ajg_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_CompensationAndRetirementDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assets measured at fair value measured on a recurring or nonrecurring basis. Includes, but is not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_FairValueAssetsMeasuredOnRecurringAndNonrecurringBasisTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of assumption used to determine benefit obligation and net periodic benefit cost of defined benefit plan. Includes, but is not limited to, discount rate, rate of compensation increase, expected long-term rate of return on plan assets and interest crediting rate. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (k) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_ScheduleOfAssumptionsUsedTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of the reconciliation of beginning and ending balances of the fair value of plan assets of pension plans and/or other employee benefit plans showing separately, if applicable, the effects during the period attributable to each of the following: actual return on plan assets, foreign currency exchange rate changes, contributions by the employer, contributions by plan participants, benefits paid, business combinations, divestitures, and settlements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (b) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_ScheduleOfChangesInFairValueOfPlanAssetsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Subparagraph (f) -Name Accounting Standards Codification -Paragraph 1 -Section 50 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480506/715-20-50-1 + Details
Name: | us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:textBlockItemType
Balance Type: | na
Period Type: | duration