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Business Combinations - Acquisition Method for Recording Business Combinations (Detail) | 6 Months Ended
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Jun. 30, 2021 USD ($) shares
Business Acquisition [Line Items] |
Common Shares Issued | shares | 152,000.0
Common Share Value | $ 19,400,000
Cash Paid | 592,000,000.0
Accrued Liability | 100,000
Escrow Deposited | 25,700,000
Recorded Earnout Payable | 49,200,000
Total Recorded Purchase Price | 686,400,000
Maximum Potential Earnout Payable | 105,500,000
Atlas General Holdings LLC [Member] |
Business Acquisition [Line Items] |
Cash Paid | 95,200,000
Escrow Deposited | 5,400,000
Recorded Earnout Payable | 8,700,000
Total Recorded Purchase Price | 109,300,000
Maximum Potential Earnout Payable | 35,000,000.0
Bollington Wilson Group [Member] |
Business Acquisition [Line Items] |
Cash Paid | 328,000,000.0
Escrow Deposited | 1,400,000
Total Recorded Purchase Price | 329,400,000
LDJ American Online Benefits Group, LLC [Member] |
Business Acquisition [Line Items] |
Cash Paid | 38,200,000
Escrow Deposited | 7,100,000
Recorded Earnout Payable | 14,800,000
Total Recorded Purchase Price | 60,100,000
Maximum Potential Earnout Payable | $ 20,000,000.0
Eleven Other Acquisitions [Member] |
Business Acquisition [Line Items] |
Common Shares Issued | shares | 152,000.0
Common Share Value | $ 19,400,000
Cash Paid | 130,600,000
Accrued Liability | 100,000
Escrow Deposited | 11,800,000
Recorded Earnout Payable | 25,700,000
Total Recorded Purchase Price | 187,600,000
Maximum Potential Earnout Payable | $ 50,500,000

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- Definition Number of shares of equity interests issued or issuable to acquire entity. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b)(4) -URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479 + Details
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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=116859721&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=116859721&loc=d3e6578-128477 + Details
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