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Commitments, Contingencies and Off-Balance Sheet Arrangements - Additional Information (Detail) | 3 Months Ended | 255 Months Ended
--- | --- | ---
Mar. 31, 2023 USD ($) ft² LetterOfCredit Entity | Mar. 31, 2022 Entity | Mar. 31, 2023 USD ($) ft² Entity LetterOfCredit
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Number of square feet | ft² | 360,000 |  | 360,000
Number of companies acquired | Entity | 22 | 31 | 660
Aggregate amount of maximum earnout obligations related to acquisitions | $ 1,748,300,000 |  |
Aggregate amount of maximum earnout obligations related to acquisitions, recorded in consolidated balance sheet | 901,800,000 |  |
Aggregate amount of earnout obligation expected settlement in cash or stock at option | 524,000,000.0 |  | $ 524,000,000.0
Aggregate amount of earnout obligation expected settlement in cash | 377,800,000 |  | $ 377,800,000
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 | 9 |  | 9
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 | 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
Letter of Credit [Member] | Collateral [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 800,000 |  | 800,000
Letter of Credit [Member] | Self-Insurance Deductibles [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 9,200,000 |  | 9,200,000
Liabilities recorded on self-insurance | 17,300,000 |  | 17,300,000
Letter of Credit [Member] | Rent-A-Captive Facility [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Debt | 2,800,000 |  | 2,800,000
Minimum [Member] | Errors And Omissions [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Actuarial range value | 5,100,000 |  | 5,100,000
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 | 6,600,000 |  | 6,600,000
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 | $ 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%
Unconsolidated Investments in Enterprises [Member] | Maximum [Member] |  |  |
Commitments Contingencies And Off Balance Sheet Arrangements [Line Items] |  |  |
Ownership interest | 50.00% |  | 50.00%

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