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Revenue from Contracts with Customers - Summary of Changes in Deferred Revenue Balances (Detail) $ in Millions | 9 Months Ended
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Sep. 30, 2018 USD ($)
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | $ 430.6
Incremental deferred revenue | 340.9
Revenue recognized during the nine-month period ended September 30, 2018 included in deferred revenue at December 31, 2017 | (312.6)
Deferred revenue recognized from business acquisitions | 13.8
Deferred revenue ending balance | 472.7
Brokerage [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 258.7
Incremental deferred revenue | 231.7
Revenue recognized during the nine-month period ended September 30, 2018 included in deferred revenue at December 31, 2017 | (207.2)
Deferred revenue recognized from business acquisitions | 13.8
Deferred revenue ending balance | 297.0
Risk Management [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 171.9
Incremental deferred revenue | 109.2
Revenue recognized during the nine-month period ended September 30, 2018 included in deferred revenue at December 31, 2017 | (105.4)
Deferred revenue ending balance | $ 175.7

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- Definition Deferred revenue, additions through business acquisitions. + References No definition available. + Details
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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 No definition available. + 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 No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of revenue recognized that was previously reported as deferred or unearned revenue. + References No definition available. + Details
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- Details
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Balance Type: |
Period Type: |

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- Details
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