Business combination aggregate earnout obligation expected settlement in cash.

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- Definition

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

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- Definition

Business Combination ,Aggregate Earnout Obligation, Maximum

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Business Combination Aggregate Earnout Obligation Recorded Maximum

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- Definition

Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]

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- Definition

Liabilities Recorded on Self-Insurance

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Number Of Letter Of Credit Issued

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- Definition

Number of square feet.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

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A credit or adjustment for government or taxing authority authorized decrease in taxes owed as a result of meeting certain tax policy conditions.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Cash received for the settlement of litigation during the current period.

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Present value of the accrual for product liability loss contingencies as of the balance sheet date (if the accrual qualifies for discounting).

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Amount of insurance benefit, claim, loss and settlement expenses incurred, as disclosed in supplementary insurance information.

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Amount of claim and benefit payable classified as other, disclosed in supplementary insurance information.

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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail)		1 Months Ended	3 Months Ended		9 Months Ended		249 Months Ended
	Sep. 29, 2022 USD ($)	Oct. 31, 2022 USD ($)	Sep. 30, 2022 USD ($) ft² LetterOfCredit Entity	Sep. 30, 2021 Entity	Sep. 30, 2022 USD ($) ft² LetterOfCredit Entity	Sep. 30, 2021 Entity	Sep. 30, 2022 USD ($) ft² Entity LetterOfCredit
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of square feet \| ft²			360,000		360,000		360,000
Number of companies acquired \| Entity			27	44	70	80	641
Aggregate amount of maximum earnout obligations related to acquisitions					$ 1,712,900,000
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet					816,300,000
Aggregate amount of earnout obligation expected settlement in cash or stock at option			$ 541,800,000		541,800,000		$ 541,800,000
Aggregate amount of earnout obligation expected settlement in cash			274,500,000		274,500,000		274,500,000
Litigation, cash settlements		$ 55,000,000.0
Litigation settlement gain, net of litigation costs and taxes		$ 35,000,000.0
Debt			$ 9,300,000		9,300,000		$ 9,300,000
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		2
Collateral [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued \| LetterOfCredit			1		1		1
Self-Insurance Deductibles [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued \| LetterOfCredit			2		2		2
Rent-A-Captive Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued \| LetterOfCredit			7		7		7
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		$ 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					10,000,000.0
Errors And Omissions [Member] \| Up to $27.0 Million [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claims, amount retained					20,000,000.0
Letter of Credit [Member] \| Security Deposit [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt			500,000		500,000		500,000
Letter of Credit [Member] \| Collateral [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt			800,000		800,000		800,000
Letter of Credit [Member] \| Self-Insurance Deductibles [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Liabilities recorded on self-insurance			17,500,000		17,500,000		17,500,000
Letter of Credit [Member] \| Rent-A-Captive Facility [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt			2,400,000		2,400,000		2,400,000
Minimum [Member] \| Errors And Omissions [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Actuarial range value			4,500,000		4,500,000		4,500,000
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		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		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		225,000,000.0
Maximum [Member] \| Errors And Omissions [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Actuarial range value			5,300,000		5,300,000		5,300,000
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		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		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			$ 400,000,000.0		$ 400,000,000.0		$ 400,000,000.0
Unconsolidated Investments in Enterprises [Member] \| Minimum [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Ownership interest			1.00%		1.00%		1.00%
Unconsolidated Investments in Enterprises [Member] \| Maximum [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Ownership interest			50.00%		50.00%		50.00%
M&T Insurance Agency [Member]
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Aggregate amount of maximum earnout obligations related to acquisitions	$ 22,500,000
Ownership interest	100.00%
Cash consideration	$ 170,000,000