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Business Combinations - Summary of Estimated Fair Values of Net Assets Acquired (Detail) $ in Millions | Dec. 31, 2017 USD ($)
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Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | $ 9.9
Other current assets | 38.2
Fixed assets | 4.6
Noncurrent assets | 0.2
Goodwill | 304.5
Expiration lists | 241.4
Non-compete agreements | 3.6
Trade names | 0.1
Total assets acquired | 602.5
Current liabilities | 37.0
Noncurrent liabilities | 19.6
Total liabilities assumed | 56.6
Total net assets acquired | 545.9
Construction Risk Solutions, LLC [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Other current assets | 3.6
Goodwill | 20.3
Expiration lists | 14.6
Non-compete agreements | 0.1
Total assets acquired | 38.6
Current liabilities | 3.2
Total liabilities assumed | 3.2
Total net assets acquired | 35.4
Hill, Chesson And Woody [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Other current assets | 2.1
Noncurrent assets | 0.2
Goodwill | 29.9
Expiration lists | 19.2
Non-compete agreements | 0.1
Total assets acquired | 51.5
Current liabilities | 0.1
Total liabilities assumed | 0.1
Total net assets acquired | 51.4
Presidio Group, Inc. [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Other current assets | 2.4
Fixed assets | 0.5
Goodwill | 25.6
Expiration lists | 27.9
Non-compete agreements | 0.1
Total assets acquired | 56.5
Current liabilities | 2.9
Total liabilities assumed | 2.9
Total net assets acquired | 53.6
Commercial Insurance Brokers [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | 0.1
Other current assets | 3.6
Fixed assets | 0.1
Goodwill | 11.7
Expiration lists | 9.0
Total assets acquired | 24.5
Current liabilities | 4.0
Total liabilities assumed | 4.0
Total net assets acquired | 20.5
Williams - Manny Insurance Group [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | 0.3
Other current assets | 1.8
Fixed assets | 0.2
Goodwill | 26.1
Expiration lists | 18.5
Non-compete agreements | 0.1
Total assets acquired | 47.0
Current liabilities | 1.6
Total liabilities assumed | 1.6
Total net assets acquired | 45.4
GPL Assurance Inc. (GPL) [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | 0.4
Other current assets | 13.6
Fixed assets | 1.0
Goodwill | 33.4
Expiration lists | 14.5
Non-compete agreements | 0.5
Trade names | 0.1
Total assets acquired | 63.5
Current liabilities | 11.6
Noncurrent liabilities | 4.1
Total liabilities assumed | 15.7
Total net assets acquired | 47.8
Lutgert Insurance (LI) [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | 0.2
Other current assets | 1.2
Fixed assets | 0.6
Goodwill | 18.9
Expiration lists | 12.9
Non-compete agreements | 0.1
Total assets acquired | 33.9
Current liabilities | 1.0
Total liabilities assumed | 1.0
Total net assets acquired | 32.9
DiBrina Group (DBG) [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Other current assets | 0.3
Fixed assets | 0.9
Goodwill | 33.5
Expiration lists | 21.6
Total assets acquired | 56.3
Current liabilities | 0.1
Total liabilities assumed | 0.1
Total net assets acquired | 56.2
31 Other Acquisitions [Member] |
Business Acquisition Actual Revenue And Pre Tax Income Loss [Line Items] |
Cash | 8.9
Other current assets | 9.6
Fixed assets | 1.3
Goodwill | 105.1
Expiration lists | 103.2
Non-compete agreements | 2.6
Total assets acquired | 230.7
Current liabilities | 12.5
Noncurrent liabilities | 15.5
Total liabilities assumed | 28.0
Total net assets acquired | $ 202.7

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- Definition Gross carrying amount before accumulated amortization as of the balance sheet date of payments made to third parties in exchange for their agreement not to engage in specified competitive practices in specified geographic territories for a specified period of time. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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