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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended		282 Months Ended
	Jun. 30, 2025 USD ($) ft² letterOfCredit acquisition	Jun. 30, 2024 USD ($) acquisition	Jun. 30, 2025 USD ($) ft² letterOfCredit acquisition	Jun. 30, 2024 USD ($) acquisition	Jun. 30, 2025 USD ($) ft² letterOfCredit company
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of square feet | ft²	360,000		360,000		360,000
Number of companies acquired	36	30	56	58	770
Aggregate amount of maximum earnout obligations related to acquisitions	$ 1,411.5		$ 1,411.5		$ 1,411.5
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet	600.3		600.3		600.3
Aggregate amount of earnout obligation expected settlement in cash or stock at option	546.7		546.7		546.7
Aggregate amount of earnout obligation expected settlement in cash	$ 53.6		$ 53.6		$ 53.6
Collateral
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued | letterOfCredit	1		1		1
Self-Insurance Deductibles
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued | letterOfCredit	1		1		1
Rent-A-Captive Facility
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Number of letters of credit issued | letterOfCredit	8		8		8
Errors And Omissions | Up to $15.0 million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claims, amount retained	$ 15.0
Errors And Omissions | Up to $2.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claims, amount retained	2.0
Errors And Omissions | Up to $10.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claims, amount retained	10.0
Errors And Omissions | Up to $20.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claims, amount retained	20.0
Letter of Credit | Security Deposit
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt	0.8		$ 0.8		$ 0.8
Letter of Credit | Self-Insurance Deductibles
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt	0.4		0.4		0.4
Liabilities recorded on self-insurance		$ 11.3		$ 11.3
Letter of Credit | Rent-A-Captive Facility
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Debt	13.0		$ 13.0		13.0
Minimum
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Business combination, earnout payable evaluation period			2 years
Minimum | Errors And Omissions
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Loss contingency accrual, product liability, net	5.9		$ 5.9		5.9
Minimum | Errors And Omissions | Up to $2.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	15.0		15.0		15.0
Minimum | Errors And Omissions | Up to $10.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	100.0		100.0		100.0
Minimum | Errors And Omissions | Up to $20.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	225.0		$ 225.0		225.0
Maximum
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Business combination, earnout payable evaluation period			3 years
Maximum | Errors And Omissions
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Loss contingency accrual, product liability, net	8.1		$ 8.1		8.1
Maximum | Errors And Omissions | Up to $2.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	100.0		100.0		100.0
Maximum | Errors And Omissions | Up to $10.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	225.0		225.0		225.0
Maximum | Errors And Omissions | Up to $20.0 Million
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Insurance claim arise during ordinary course of business	$ 400.0		$ 400.0		$ 400.0
Unconsolidated Investments in Enterprises | Minimum
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Ownership interest	1.00%		1.00%		1.00%
Unconsolidated Investments in Enterprises | Maximum
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items]
Ownership interest	50.00%		50.00%		50.00%

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