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Business Combinations - Acquisition Method for Recording Business Combinations (Detail) | 12 Months Ended
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Dec. 31, 2024 USD ($) shares
Ericson Insurance Services [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 129
Common Share Value | $ 30,100,000
Cash Paid | 26,500,000
Escrow Deposited | 3,000,000
Recorded Earnout Payable | 7,300,000
Total Recorded Purchase Price | 66,900,000
Maximum Potential Earnout Payable | 10,000,000.0
The Rowley Agency [Member] |
Business Acquisition [Line Items] |
Cash Paid | 117,200,000
Escrow Deposited | 11,000,000.0
Total Recorded Purchase Price | 128,200,000
Operationsinc [Member] |
Business Acquisition [Line Items] |
Cash Paid | 52,600,000
Escrow Deposited | 2,800,000
Recorded Earnout Payable | 11,000,000
Total Recorded Purchase Price | 66,400,000
Maximum Potential Earnout Payable | 20,000,000
RIBV Holdings [Member] |
Business Acquisition [Line Items] |
Cash Paid | 171,400,000
Accrued Liability | 6,500,000
Escrow Deposited | 5,100,000
Recorded Earnout Payable | 24,300,000
Total Recorded Purchase Price | 207,300,000
Maximum Potential Earnout Payable | 50,000,000
Redington Limited [Member] |
Business Acquisition [Line Items] |
Cash Paid | 199,300,000
Accrued Liability | 400,000
Escrow Deposited | 700,000
Total Recorded Purchase Price | $ 200,400,000
Forty-three Other Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 231,000
Common Share Value | $ 48,800,000
Cash Paid | 806,500,000
Accrued Liability | 9,100,000
Escrow Deposited | 44,400,000
Recorded Earnout Payable | 121,800,000
Total Recorded Purchase Price | 1,030,600,000
Maximum Potential Earnout Payable | $ 288,600,000
2024 Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 360,000
Common Share Value | $ 78,900,000
Cash Paid | 1,373,500,000
Accrued Liability | 16,000,000.0
Escrow Deposited | 67,000,000.0
Recorded Earnout Payable | 164,400,000
Total Recorded Purchase Price | 1,699,800,000
Maximum Potential Earnout Payable | $ 368,600,000

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- Definition The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 954 -SubTopic 440 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478522/954-440-50-1 + Details
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