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v3.23.2

Business Combinations - Additional Information (Detail) $ in Millions |  | 3 Months Ended | 6 Months Ended | 258 Months Ended
--- | --- | --- | --- | ---
Apr. 03, 2023 Employee | Jun. 30, 2023 USD ($) Entity | Jun. 30, 2022 USD ($) Entity | Jun. 30, 2023 USD ($) Entity | Jun. 30, 2022 USD ($) Entity | Jun. 30, 2023 USD ($) Entity
Business Acquisition [Line Items] |  |  |  |  |  |
Accretion of the discount on acquisition |  | $ 19.8 | $ 14.0 | $ 39.6 | $ 23.4 |
Income (expense) related to net adjustments to estimated fair value of liability for earnout obligations |  | $ 10.4 | $ 47.8 | $ (11.6) | $ 36.3 |
Number of companies acquired | Entity |  | 34 | 30 | 45 | 50 | 675
Aggregate amount of maximum earnout obligations related to acquisitions |  |  |  | $ 1,899.1 |  |
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet |  |  |  | 990.8 |  |
Aggregate amount of earnout obligation expected settlement in cash or stock at option |  | $ 571.4 |  | 571.4 |  | $ 571.4
Aggregate amount of earnout obligation expected settlement in cash |  | 419.4 |  | 419.4 |  | 419.4
Goodwill |  | 858.7 |  | 858.7 |  | 858.7
Expiration lists |  | 549.9 |  | 549.9 |  | 549.9
Non-compete agreements |  | 11.4 |  | 11.4 |  | 11.4
Trade names |  | 3.9 |  | 3.9 |  | 3.9
Total revenues |  | 2,447.6 | $ 2,146.3 | 5,250.6 | $ 4,686.8 |
Brokerage Management [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Goodwill |  | 858.7 |  | 858.7 |  | 858.7
Expiration lists |  | 549.9 |  | 549.9 |  | 549.9
Non-compete agreements |  | 11.4 |  | 11.4 |  | 11.4
Trade names |  | 3.9 |  | 3.9 |  | 3.9
Brokerage and Risk Management [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Write-off of amortizable intangible assets |  |  |  | 3.2 | $ 0.4 |
Brokerage [Member] | Expiration Lists [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Business acquisition not deductible for income tax purposes |  | 413.7 |  | 413.7 |  | 413.7
Brokerage [Member] | Non-Compete Agreements [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Business acquisition not deductible for income tax purposes |  | 10.6 |  | 10.6 |  | 10.6
Brokerage [Member] | Trade Names [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Business acquisition not deductible for income tax purposes |  | $ 2.6 |  | $ 2.6 |  | $ 2.6
Minimum [Member] | Expiration Lists [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 2 years |  | 2 years |  | 2 years
Minimum [Member] | Non-Compete Agreements [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 2 years |  | 2 years |  | 2 years
Minimum [Member] | Trade Names [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 2 years |  | 2 years |  | 2 years
Maximum [Member] | Expiration Lists [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 15 years |  | 15 years |  | 15 years
Maximum [Member] | Non-Compete Agreements [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 6 years |  | 6 years |  | 6 years
Maximum [Member] | Trade Names [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Estimated useful lives of intangibles assets, years |  | 15 years |  | 15 years |  | 15 years
2023 Acquisitions [Member] | Valuation, Market Approach [Member] | Measurement Input, Discount Rate [Member] | Minimum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.05 |  | 0.05 |  | 0.05
2023 Acquisitions [Member] | Valuation, Market Approach [Member] | Measurement Input, Discount Rate [Member] | Maximum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.20 |  | 0.20 |  | 0.20
2023 Acquisitions [Member] | Valuation, Income Approach | Measurement Input, Discount Rate [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.09 |  | 0.09 |  | 0.09
2022 Acquisitions [Member] | Valuation, Market Approach [Member] | Measurement Input, Long-term Revenue Growth Rate [Member] | Minimum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.03 |  | 0.03 |  | 0.03
2022 Acquisitions [Member] | Valuation, Market Approach [Member] | Measurement Input, Long-term Revenue Growth Rate [Member] | Maximum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.05 |  | 0.05 |  | 0.05
2022 Acquisitions [Member] | Valuation, Income Approach | Minimum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Attrition rate |  |  |  | 5.00% |  |
2022 Acquisitions [Member] | Valuation, Income Approach | Maximum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Attrition rate |  |  |  | 25.50% |  |
2022 Acquisitions [Member] | Valuation, Income Approach | Measurement Input, Long-term Revenue Growth Rate [Member] | Minimum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.09 |  | 0.09 |  | 0.09
2022 Acquisitions [Member] | Valuation, Income Approach | Measurement Input, Long-term Revenue Growth Rate [Member] | Maximum [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Measurement input |  | 0.11 |  | 0.11 |  | 0.11
Business Acquisition [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Annualized revenue of business acquisitions |  |  |  | $ 418.1 |  |
Total revenues |  |  |  | 110.3 |  |
Net earnings |  |  |  | (11.3) |  |
Business Acquisition [Member] | Brokerage [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Expiration lists |  | $ 549.9 |  | 549.9 |  | $ 549.9
Non-compete agreements |  | 11.4 |  | 11.4 |  | 11.4
Trade names |  | 3.9 |  | 3.9 |  | 3.9
Deferred tax liability |  | $ 105.4 |  | $ 105.4 |  | $ 105.4
BCHR Holdings, L.P [Member] |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |
Number of employees | Employee | 2,300 |  |  |  |  |
Number of employees with credentialed actuaries | Employee | 220 |  |  |  |  |

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