XML 80 R70.htm IDEA: XBRL DOCUMENT
v3.22.1

Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) | 3 Months Ended | 243 Months Ended
--- | --- | ---
Mar. 31, 2022 USD ($) ft² Entity Employee LetterOfCredit | Mar. 31, 2021 Entity | Mar. 31, 2022 USD ($) ft² Entity LetterOfCredit
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of square feet | ft² | 360,000 |  | 360,000
Number of employees will accommodate at new facility | Employee | 2,000 |  |
Number of companies acquired | Entity | 31 | 25 | 626
Aggregate amount of maximum earnout obligations related to acquisitions | $ 1,823,000,000.0 |  |
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet | 962,300,000 |  |
Aggregate amount of earnout obligation expected settlement in cash or stock at option | 646,500,000 |  | $ 646,500,000
Aggregate amount of earnout obligation expected settlement in cash | 315,800,000 |  | $ 315,800,000
Income tax credits and adjustments | $ 108,000,000.0 |  |
Security Deposit [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 2 |  | 2
Collateral [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 1 |  | 1
Self-Insurance Deductibles [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 2 |  | 2
Rent-A-Captive Facility [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 8 |  | 8
Errors And Omissions [Member] | Up to $4.5 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claims, amount retained | $ 2,000,000.0 |  |
Errors And Omissions [Member] | Up to $10 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claims, amount retained | 15,000,000.0 |  |
Insurance claim arise during ordinary course of business | 15,000,000.0 |  | $ 15,000,000.0
Errors And Omissions [Member] | Up to $20.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claims, amount retained | 20,000,000.0 |  |
Errors And Omissions [Member] | Up to $27.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claims, amount retained | 10,000,000.0 |  |
Letter of Credit [Member] | Security Deposit [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 500,000 |  | 500,000
Letter of Credit [Member] | Collateral [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 900,000 |  | 900,000
Letter of Credit [Member] | Self-Insurance Deductibles [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 9,400,000 |  | 9,400,000
Liabilities recorded on self-insurance | 16,600,000 |  | 16,600,000
Letter of Credit [Member] | Rent-A-Captive Facility [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 6,200,000 |  | 6,200,000
Minimum [Member] | Errors And Omissions [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Actuarial range value | 3,600,000 |  | 3,600,000
Minimum [Member] | Errors And Omissions [Member] | Up to $4.5 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | 15,000,000.0 |  | 15,000,000.0
Minimum [Member] | Errors And Omissions [Member] | Up to $20.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | 100,000,000.0 |  | 100,000,000.0
Minimum [Member] | Errors And Omissions [Member] | Up to $27.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | 225,000,000.0 |  | 225,000,000.0
Maximum [Member] | Errors And Omissions [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Actuarial range value | 5,900,000 |  | 5,900,000
Maximum [Member] | Errors And Omissions [Member] | Up to $4.5 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | 100,000,000.0 |  | 100,000,000.0
Maximum [Member] | Errors And Omissions [Member] | Up to $20.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | 225,000,000.0 |  | 225,000,000.0
Maximum [Member] | Errors And Omissions [Member] | Up to $27.0 Million [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Insurance claim arise during ordinary course of business | $ 365,000,000.0 |  | $ 365,000,000.0
Unconsolidated Investments in Enterprises [Member] | Minimum [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Ownership interest | 1.00% |  | 1.00%
Unconsolidated Investments in Enterprises [Member] | Maximum [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Ownership interest | 50.00% |  | 50.00%

X
- Definition Business combination aggregate earnout obligation expected settlement in cash. + References No definition available. + Details
Name: | ajg_BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCash
Namespace Prefix: | ajg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Business combination aggregate earnout obligation expected settlement in cash or stock at option. + References No definition available. + Details
Name: | ajg_BusinessCombinationAggregateEarnoutObligationExpectedSettlementInCashOrStockAtOption
Namespace Prefix: | ajg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Business Combination ,Aggregate Earnout Obligation, Maximum + References No definition available. + Details
Name: | ajg_BusinessCombinationAggregateEarnoutObligationMaximum
Namespace Prefix: | ajg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Business Combination Aggregate Earnout Obligation Recorded Maximum + References No definition available. + Details
Name: | ajg_BusinessCombinationAggregateEarnoutObligationRecordedMaximum
Namespace Prefix: | ajg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] + References No definition available. + Details
Name: | ajg_CommitmentsContingenciesAndOffBalanceSheetArrangementsLineItems
Namespace Prefix: | ajg_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Liabilities Recorded on Self-Insurance + References No definition available. + Details
Name: | ajg_LiabilitiesRecordedOnSelfInsurance
Namespace Prefix: | ajg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Number of employees. + References No definition available. + Details
Name: | ajg_NumberOfEmployees
Namespace Prefix: | ajg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Letter Of Credit Issued + References No definition available. + Details
Name: | ajg_NumberOfLetterOfCreditIssued
Namespace Prefix: | ajg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of square feet. + References No definition available. + Details
Name: | ajg_NumberOfSquareFeet
Namespace Prefix: | ajg_
Data Type: | dtr-types:areaItemType
Balance Type: | na
Period Type: | instant

X
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
Name: | us-gaap_IncomeTaxCreditsAndAdjustments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69C -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 55 -Paragraph 69B -URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611 Reference 7: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The number of businesses acquired by the entity during the period. + References No definition available. + Details
Name: | us-gaap_NumberOfBusinessesAcquired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Present value of the accrual for product liability loss contingencies as of the balance sheet date (if the accrual qualifies for discounting). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.Y.Q1) -URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751 + Details
Name: | us-gaap_ProductLiabilityContingencyAccrualPresentValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of insurance benefit, claim, loss and settlement expenses incurred, as disclosed in supplementary insurance information. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16(Column H)) -URI http://asc.fasb.org/extlink&oid=120401096&loc=d3e574960-122915 + Details
Name: | us-gaap_SupplementaryInsuranceInformationBenefitsClaimsLossesAndSettlementExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of claim and benefit payable classified as other, disclosed in supplementary insurance information. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 235 -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-16(Column E)) -URI http://asc.fasb.org/extlink&oid=120401096&loc=d3e574960-122915 + Details
Name: | us-gaap_SupplementaryInsuranceInformationOtherPolicyClaimsAndBenefitsPayable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_InvestmentTypeAxis=ajg_SecurityDepositMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_CollateralAxis=us-gaap_CollateralPledgedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=ajg_SelfInsuranceDeductiblesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=ajg_RentCaptiveFacilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LineOfCreditFacilityAxis=ajg_ErrorsAndOmissionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=ajg_UpToFourPointFiveMillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=ajg_UpToTenMillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=ajg_UpToTwentyPointZeroMillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_OtherCommitmentsAxis=ajg_UpToTwentySevenPointZeroMillionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ShortTermDebtTypeAxis=us-gaap_LetterOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ajg_UnconsolidatedInvestmentsInEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |