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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- Definition

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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- Definition

Number of employees.

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No definition available.

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- Definition

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

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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- 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.

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- Definition

The number of businesses acquired by the entity during the 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)	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%