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Contracts with Customers - Summary of Changes in Deferred Revenue Balances (Detail) $ in Millions | 9 Months Ended
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Sep. 30, 2025 USD ($)
Change in Contract with Customer, Liability [Roll Forward] |
Deferred revenue beginning balance | $ 604.3
Incremental deferred revenue | 434.8
Revenue recognized during the nine-month period ended September 30, 2025 included in deferred revenue at December 31, 2024 | (403.1)
Net change in collected billings/deposits received from customers | 7.4
Impact of change in foreign exchange rates | 27.3
Deferred revenue recognized from business acquisitions | 220.4
Deferred revenue ending balance | 891.1
Brokerage |
Change in Contract with Customer, Liability [Roll Forward] |
Deferred revenue beginning balance | 430.9
Incremental deferred revenue | 351.9
Revenue recognized during the nine-month period ended September 30, 2025 included in deferred revenue at December 31, 2024 | (328.8)
Net change in collected billings/deposits received from customers | 9.1
Impact of change in foreign exchange rates | 26.4
Deferred revenue recognized from business acquisitions | 220.4
Deferred revenue ending balance | 709.9
Risk Management |
Change in Contract with Customer, Liability [Roll Forward] |
Deferred revenue beginning balance | 173.4
Incremental deferred revenue | 82.9
Revenue recognized during the nine-month period ended September 30, 2025 included in deferred revenue at December 31, 2024 | (74.3)
Net change in collected billings/deposits received from customers | (1.7)
Impact of change in foreign exchange rates | 0.9
Deferred revenue recognized from business acquisitions | 0.0
Deferred revenue ending balance | $ 181.2

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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479837/606-10-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-8 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479837/606-10-45-2 + Details
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