Business Acquisition Purchase Price Allocation Goodwill Not Expected Tax Deductible Amount

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- Definition

Business Acquisitions Purchase Price Allocation Goodwill Amount

+ References

No definition available.

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- Definition

Business acquisitionsnet earnings before interest, income taxes, depreciation, amortization and change in estimated acquisition earnout payables.

+ References

No definition available.

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- Definition

Business combination aggregate earnout obligation expected settlement in cash.

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Business Combination ,Aggregate Earnout Obligation, Maximum

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No definition available.

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- Definition

Business Combination Aggregate Earnout Obligation Recorded Maximum

+ References

No definition available.

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- Definition

Business Combination, Annualize Revenue

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No definition available.

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- Definition

Business combination, recognized identifiable assets acquired and liabilities assumed, intangible assets, expiration lists.

+ References

No definition available.

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- Definition

Business combination, recognized identifiable assets acquired and liabilities assumed, intangible assets, non-compete agreements.

+ References

No definition available.

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- Definition

Business combination, recognized identifiable assets acquired and liabilities assumed, intangible assets, trade names.

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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

Value of input used to measure alternative investment.

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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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- 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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- 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

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences.

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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.

+ References

No definition available.

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- Definition

Amount of increase (decrease) from measurement period adjustment of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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- Definition

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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-Topic 350
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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		9 Months Ended		12 Months Ended	273 Months Ended
	Sep. 30, 2024 USD ($) Entity	Sep. 30, 2023 USD ($) Entity	Sep. 30, 2024 USD ($) Entity	Sep. 30, 2023 USD ($) Entity	Dec. 31, 2023 USD ($)	Sep. 30, 2024 USD ($) Entity
Business Acquisition [Line Items]
Accretion of the discount on acquisition	$ 13.8	$ 17.9	$ 47.6	$ 57.5
Income (expense) related to net adjustments to estimated fair value of liability for earnout obligations	$ 29.1	$ 20.4	$ 60.2	$ 8.8
Number of companies acquired \| Entity	29	20	74	59		729
Aggregate amount of maximum earnout obligations related to acquisitions			$ 1,931.8
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet			1,221.1
Aggregate amount of earnout obligation expected settlement in cash or stock at option	$ 475.5		475.5			$ 475.5
Aggregate amount of earnout obligation expected settlement in cash	745.6		745.6			745.6
Goodwill	410.7		410.7			410.7
Expiration lists	368.1		368.1			368.1
Non-compete agreements	8.6		8.6			8.6
Trade names	0.3		0.3			0.3
Net increase to goodwill			188.9		$ 256.7
Total revenues	2,809.2	$ 2,537.4	8,891.5	$ 7,780.6
Brokerage [Member]
Business Acquisition [Line Items]
Net increase to goodwill			87.4
Write-off of amortizable intangible assets	5.4	$ 0.1	19.4	$ 3.3
Brokerage [Member] \| Expiration Lists [Member]
Business Acquisition [Line Items]
Business acquisition not deductible for income tax purposes	52.1		52.1			52.1
Brokerage [Member] \| Non-Compete Agreements [Member]
Business Acquisition [Line Items]
Business acquisition not deductible for income tax purposes	4.1		4.1			4.1
Brokerage [Member] \| Trade Names [Member]
Business Acquisition [Line Items]
Business acquisition not deductible for income tax purposes	$ 0.3		$ 0.3			$ 0.3
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
2024 Acquisitions [Member] \| Valuation, Market Approach [Member] \| Measurement Input, Discount Rate [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Measurement input	0.03		0.03			0.03
2024 Acquisitions [Member] \| Valuation, Market Approach [Member] \| Measurement Input, Discount Rate [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Measurement input	0.15		0.15			0.15
2024 Acquisitions [Member] \| Valuation, Income Approach \| Measurement Input, Discount Rate [Member]
Business Acquisition [Line Items]
Measurement input	0.09		0.09			0.09
2023 Acquisitions [Member] \| Valuation, Market Approach [Member] \| Measurement Input, Long-term Revenue Growth Rate [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Measurement input	0.007		0.007			0.007
2023 Acquisitions [Member] \| Valuation, Market Approach [Member] \| Measurement Input, Long-term Revenue Growth Rate [Member] \| Maximum [Member]
Business Acquisition [Line Items]
Measurement input	0.053		0.053			0.053
2023 Acquisitions [Member] \| Valuation, Income Approach \| Minimum [Member]
Business Acquisition [Line Items]
Attrition rate			5.00%
2023 Acquisitions [Member] \| Valuation, Income Approach \| Maximum [Member]
Business Acquisition [Line Items]
Attrition rate			11.00%
2023 Acquisitions [Member] \| Valuation, Income Approach \| Measurement Input, Long-term Revenue Growth Rate [Member] \| Minimum [Member]
Business Acquisition [Line Items]
Measurement input	0.095		0.095			0.095
2023 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			$ 187.9
Total revenues			84.8
Net earnings			(9.2)
Net earnings before interest, income taxes, depreciation, amortization and change in estimated acquisition earnout payables			15.2
Business Acquisition [Member] \| Brokerage [Member]
Business Acquisition [Line Items]
Expiration lists	$ 368.1		368.1			$ 368.1
Non-compete agreements	8.6		8.6			8.6
Trade names	0.3		0.3			0.3
Deferred tax liability	$ 13.1		$ 13.1			$ 13.1