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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) $ in Millions | 3 Months Ended | 9 Months Ended | 285 Months Ended
--- | --- | --- | ---
Sep. 30, 2025 USD ($) ft² letterOfCredit acquisition | Sep. 30, 2024 USD ($) acquisition | Sep. 30, 2025 USD ($) ft² letterOfCredit acquisition | Sep. 30, 2024 USD ($) acquisition | Sep. 30, 2025 USD ($) ft² company 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 | 41 | 29 | 82 | 74 | 776
Aggregate amount of maximum earnout obligations related to acquisitions | $ 1,723.1 |  | $ 1,723.1 |  | $ 1,723.1
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet | 823.5 |  | 823.5 |  | 823.5
Aggregate amount of earnout obligation expected settlement in cash or stock at option | 557.9 |  | 557.9 |  | 557.9
Aggregate amount of earnout obligation expected settlement in cash | $ 265.6 |  | $ 265.6 |  | $ 265.6
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 | 10 |  | 10 |  | 10
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 | 0.3 |  | 0.3 |  | 0.3
Liabilities recorded on self-insurance |  | $ 12.0 |  | $ 12.0 |
Letter of Credit | Rent-A-Captive Facility |  |  |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |  |  |
Debt | 13.2 |  | $ 13.2 |  | 13.2
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 | 6.2 |  | $ 6.2 |  | 6.2
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 | 7.7 |  | $ 7.7 |  | 7.7
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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