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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) | 12 Months Ended
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Dec. 31, 2024 USD ($) ft² Employee LetterOfCredit | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of square feet | ft² | 360,000 |  |
Number of employees will accommodate at new facility | Employee | 2,000 |  |
Total rent expense | $ 183,400,000 | $ 183,500,000 | $ 176,600,000
Aggregate amount of maximum earnout obligations related to acquisitions | 1,998,200,000 | 2,009,800,000 |
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet | 1,302,000,000 | 1,294,200,000 |
Aggregate amount of earnout obligation expected settlement in cash or common stock at option | 511,900,000 | 564,800,000 |
Aggregate amount of earnout obligation expected settlement in cash | 790,100,000 | $ 729,400,000 |
Debt | 23,000,000.0 |  |
Liabilities recorded on self-insurance | $ 12,000,000.0 |  |
Collateral [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 1 |  |
Self-Insurance Deductibles [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 2 |  |
Rent-A-Captive Facility [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of letters of credit issued | LetterOfCredit | 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 |  |
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 | 800,000 |  |
Letter of Credit [Member] | Self-Insurance Deductibles [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 9,200,000 |  |
Liabilities recorded on self-insurance | 12,000,000 |  |
Letter of Credit [Member] | Rent-A-Captive Facility [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 13,000,000 |  |
Minimum [Member] | Errors And Omissions [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Loss Contingency Accrual, Product Liability, Net, Total | 10,700,000 |  |
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 |  |
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 |  |
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 |  |
Minimum [Member] | Unconsolidated Investments in Enterprises [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Ownership interest | 1.00% |  |
Maximum [Member] | Errors And Omissions [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Loss Contingency Accrual, Product Liability, Net, Total | $ 4,400,000 |  |
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 |  |
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 |  |
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 |  |
Maximum [Member] | Unconsolidated Investments in Enterprises [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Ownership interest | 50.00% |  |
Tax Increment Financing [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Property tax credits receivable period | 15 years |  |
Economic development for growing economy tax credit | $ 62,600,000 |  |
Tax Increment Financing [Member] | Minimum [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Property tax credit expect to receive | 50,000,000 |  |
Tax Increment Financing [Member] | Maximum [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Property tax credit expect to receive | $ 80,000,000 |  |

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