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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, 2018 USD ($) shares
Business Acquisition [Line Items] |
Common Shares Issued | shares | 826
Common Share Value | $ 54,200,000
Cash Paid | 792,200,000
Accrued Liability | 3,100,000
Escrow Deposited | 71,400,000
Recorded Earnout Payable | 94,000,000
Total Recorded Purchase Price | 1,014,900,000
Maximum Potential Earnout Payable | $ 201,500,000
Market Financial Group, Ltd and Austin Consulting Group Inc. (MFG) [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 53
Common Share Value | $ 3,700,000
Cash Paid | 33,900,000
Escrow Deposited | 4,200,000
Recorded Earnout Payable | 2,700,000
Total Recorded Purchase Price | 44,500,000
Maximum Potential Earnout Payable | 7,000,000
McGregor & Associates (M&A) [Member] |
Business Acquisition [Line Items] |
Cash Paid | 13,500,000
Escrow Deposited | 2,500,000
Recorded Earnout Payable | 5,100,000
Total Recorded Purchase Price | 21,100,000
Maximum Potential Earnout Payable | 12,000,000
Pronto Insurance (PI) [Member] |
Business Acquisition [Line Items] |
Cash Paid | 294,800,000
Escrow Deposited | 18,700,000
Total Recorded Purchase Price | $ 313,500,000
Reassurance Holdings, Inc (RHI) [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 343
Common Share Value | $ 24,400,000
Cash Paid | 84,400,000
Escrow Deposited | 13,300,000
Recorded Earnout Payable | 3,300,000
Total Recorded Purchase Price | 125,400,000
Maximum Potential Earnout Payable | 21,500,000
Buckman Mitchell, Inc. (BMI) [Member] |
Business Acquisition [Line Items] |
Cash Paid | 43,900,000
Escrow Deposited | 1,900,000
Recorded Earnout Payable | 3,600,000
Total Recorded Purchase Price | 49,400,000
Maximum Potential Earnout Payable | 8,500,000
Accompass Inc. (AI) [Member] |
Business Acquisition [Line Items] |
Cash Paid | 29,800,000
Escrow Deposited | 2,600,000
Recorded Earnout Payable | 4,400,000
Total Recorded Purchase Price | 36,800,000
Maximum Potential Earnout Payable | $ 11,300,000
42 Other Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 430
Common Share Value | $ 26,100,000
Cash Paid | 291,900,000
Accrued Liability | 3,100,000
Escrow Deposited | 28,200,000
Recorded Earnout Payable | 74,900,000
Total Recorded Purchase Price | 424,200,000
Maximum Potential Earnout Payable | $ 141,200,000

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- Definition Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6613-128477 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=109124213&loc=d3e6578-128477 + Details
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