Business Acquisition Purchase Price Allocation Goodwill Not Expected Tax Deductible Amount

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- Definition

Business Acquisitions Purchase Price Allocation Goodwill Amount

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No definition available.

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- Definition

Business combination aggregate earnout obligation expected settlement in cash.

+ References

No definition available.

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- Definition

Business combination aggregate earnout obligation expected settlement in cash or stock at option.

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No definition available.

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- Definition

Business Combination ,Aggregate Earnout Obligation, Maximum

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- Definition

Business Combination Aggregate Earnout Obligation Recorded Maximum

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No definition available.

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Business Combination, Annualize Revenue

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- Definition

Expiration lists

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No definition available.

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- Definition

Fair Value Inputs, Attrition Rate

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No definition available.

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- Definition

Number of employee with credentialed actuaries.

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No definition available.

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Number of employees.

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No definition available.

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- Definition

Value of input used to measure alternative investment.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 805
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- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

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-Topic 805
-SubTopic 10
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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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- Definition

For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of deferred tax liability attributable to taxable temporary differences.

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-Topic 740
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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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- Definition

Gross carrying amount before accumulated amortization as of the balance sheet date of payments made to third parties in exchange for their agreement not to engage in specified competitive practices in specified geographic territories for a specified period of time.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 350
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Gross carrying amount before accumulated amortization as of the balance sheet date of the rights acquired through registration of a trade name to gain or protect exclusive use thereof for a reasonably expected period of economic benefit.

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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
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- Definition

The number of businesses acquired by the entity during the period.

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No definition available.

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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