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Business Combinations - Acquisition Method for Recording Business Combinations (Detail) shares in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) shares
First Ireland Risk Management Ltd [Member] |
Business Acquisition [Line Items] |
Cash Paid | $ 86,400,000
Escrow Deposited | 5,300,000
Recorded Earnout Payable | 6,100,000
Total Recorded Purchase Price | 97,800,000
Maximum Potential Earnout Payable | 6,600,000
BCHR Holdings, L.P. dba Buck [Member] |
Business Acquisition [Line Items] |
Cash Paid | 600,800,000
Accrued Liability | 500,000
Escrow Deposited | 19,500,000
Total Recorded Purchase Price | $ 620,800,000
Boley-Featherston-Huffman & Deal Co. [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 243
Common Share Value | $ 45,200,000
Cash Paid | 8,800,000
Escrow Deposited | 6,000,000
Recorded Earnout Payable | 9,300,000
Total Recorded Purchase Price | 69,300,000
Maximum Potential Earnout Payable | 15,000,000
Tay River Holdings Limited [Member] |
Business Acquisition [Line Items] |
Cash Paid | 40,300,000
Accrued Liability | 4,300,000
Escrow Deposited | 2,400,000
Recorded Earnout Payable | 32,000,000.0
Total Recorded Purchase Price | 79,000,000.0
Maximum Potential Earnout Payable | $ 88,700,000
Insurance By Ken Brown [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 273
Common Share Value | $ 53,900,000
Cash Paid | 1,800,000
Escrow Deposited | 2,900,000
Recorded Earnout Payable | 11,300,000
Total Recorded Purchase Price | 69,900,000
Maximum Potential Earnout Payable | $ 17,500,000
RHP General Agency [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 335
Common Share Value | $ 65,700,000
Cash Paid | 1,300,000
Escrow Deposited | 5,000,000
Recorded Earnout Payable | 4,400,000
Total Recorded Purchase Price | 76,400,000
Maximum Potential Earnout Payable | $ 11,000,000
Clements & Co [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 193
Common Share Value | $ 43,300,000
Cash Paid | 7,100,000
Escrow Deposited | 3,000,000
Recorded Earnout Payable | 30,900,000
Total Recorded Purchase Price | 84,300,000
Maximum Potential Earnout Payable | 70,000,000
Eastern Insurance Group, LLC [Member] |
Business Acquisition [Line Items] |
Cash Paid | 511,400,000
Accrued Liability | 3,700,000
Total Recorded Purchase Price | 515,100,000
Cadence Insurance, Inc. [Member] |
Business Acquisition [Line Items] |
Cash Paid | 880,100,000
Accrued Liability | 5,900,000
Total Recorded Purchase Price | 886,000,000
My Plan Manager [Member] |
Business Acquisition [Line Items] |
Cash Paid | 298,600,000
Escrow Deposited | 3,000,000
Total Recorded Purchase Price | $ 301,600,000
Forty-one Other Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 450
Common Share Value | $ 98,000,000
Cash Paid | 671,600,000
Accrued Liability | 11,700,000
Escrow Deposited | 47,600,000
Recorded Earnout Payable | 113,500,000
Total Recorded Purchase Price | 942,400,000
Maximum Potential Earnout Payable | $ 191,400,000
2023 Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 1,494
Common Share Value | $ 306,100,000
Cash Paid | 3,108,200,000
Accrued Liability | 26,100,000
Escrow Deposited | 94,700,000
Recorded Earnout Payable | 207,500,000
Total Recorded Purchase Price | 3,742,600,000
Maximum Potential Earnout Payable | $ 400,200,000

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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://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//1943274/2147480327/954-440-50-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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