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Revenue from Contracts with Customers - Summary of Changes in Deferred Revenue Balances (Detail) $ in Millions | 3 Months Ended
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Mar. 31, 2018 USD ($)
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | $ 430.6
Incremental deferred revenue | 182.5
Revenue recognized during the three-month period ended March 31, 2018 included in deferred revenue at December 31, 2017 | (148.6)
Deferred revenue recognized from business acquisitions | 0.7
Deferred revenue ending balance | 465.2
Brokerage [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 258.7
Incremental deferred revenue | 144.6
Revenue recognized during the three-month period ended March 31, 2018 included in deferred revenue at December 31, 2017 | (115.9)
Deferred revenue recognized from business acquisitions | 0.7
Deferred revenue ending balance | 288.1
Risk Management [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 171.9
Incremental deferred revenue | 37.9
Revenue recognized during the three-month period ended March 31, 2018 included in deferred revenue at December 31, 2017 | (32.7)
Deferred revenue ending balance | $ 177.1

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- Definition Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.3) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.4(a).Q1) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 + Details
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- Definition Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 13.A.4(a).Q1) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.3) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 + Details
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