Contracts with Customers (Tables)

3 Months Ended

Mar. 31, 2021

Revenue From Contract With Customer [Abstract]

Summary of Unbilled Receivables, Contract Assets and Contract Liabilities from Contracts with Customers

Information about unbilled receivables, contract assets and contract liabilities from contracts with customers is as follows (in millions):

	March 31, 2021		December 31, 2020
Unbilled receivables	$	911.1	$	603.1
Deferred contract costs		65.4		102.0
Deferred revenue		590.7		541.3

Summary of Changes in Deferred Revenue Balances

Significant changes in the deferred revenue balances, which include foreign currency translation adjustments, during the period are as follows (in millions):

				Risk
	Brokerage			Management			Total
Deferred revenue at December 31, 2020	$	354.7		$	186.6		$	541.3
Incremental deferred revenue		188.3			26.4			214.7
Revenue recognized during the three-month period ended March 31, 2021 included in deferred revenue at December 31, 2020		(167.6	)		(25.3	)		(192.9	)
Net change in collected billings/deposits received from customers		5.6			10.5			16.1
Impact of change in foreign exchange rates		4.1			0.3			4.4
Deferred revenue recognized from business acquisitions		7.1			—			7.1
Deferred revenue at March 31, 2021	$	392.2		$	198.5		$	590.7

Summary of Expected Revenue Related to Performance Obligations

The estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) at the end of the reporting period is as follows (in millions):

	Brokerage		Risk Management		Total
2021 (remaining nine months)	$	329.5	$	123.8	$	453.3
2022		43.4		37.2		80.6
2023		17.8		16.7		34.5
2024		0.7		7.6		8.3
2025		0.4		4.5		4.9
Thereafter		0.4		8.7		9.1
Total	$	392.2	$	198.5	$	590.7