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Revenue from Contracts with Customers - Summary of Changes in Deferred Revenue Balances (Detail) $ in Millions | 6 Months Ended
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Jun. 30, 2018 USD ($)
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | $ 430.6
Incremental deferred revenue | 277.5
Revenue recognized during the six-month period ended June 30, 2018 included in deferred revenue at December 31, 2017 | (249.2)
Deferred revenue recognized from business acquisitions | 12.9
Deferred revenue ending balance | 471.8
Brokerage [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 258.7
Incremental deferred revenue | 204.1
Revenue recognized during the six-month period ended June 30, 2018 included in deferred revenue at December 31, 2017 | (181.0)
Deferred revenue recognized from business acquisitions | 12.9
Deferred revenue ending balance | 294.7
Risk Management [Member] |
Deferred Revenue Arrangement [Line Items] |
Deferred revenue beginning balance | 171.9
Incremental deferred revenue | 73.4
Revenue recognized during the six-month period ended June 30, 2018 included in deferred revenue at December 31, 2017 | (68.2)
Deferred revenue ending balance | $ 177.1

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- Definition Deferred revenue, additions through business acquisitions. + References No definition available. + Details
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Balance Type: | credit
Period Type: | duration

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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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Data Type: | xbrli:monetaryItemType
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- Details
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Balance Type: |
Period Type: |

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- Details
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