Revenue (Tables)

12 Months Ended

Dec. 31, 2019

Revenue from Contract with Customer [Abstract]

Disaggregation of Revenue

The following tables disaggregate revenue by reportable segment and service line (in millions):

		Year Ended December 31, 2019
	Revenue recognition timing	Americas		EMEA		APAC		Total
Property, facilities and project management	Over time	$	3,723.2	$	412.8	$	1,141.0	$	5,277.0
Leasing	At a point in time	1,519.0		251.5		180.3		1,950.8
Capital markets	At a point in time	746.9		182.2		104.6		1,033.7
Valuation and other	At a point in time or over time	183.0		191.7		114.8		489.5
Total revenue		$	6,172.1	$	1,038.2	$	1,540.7	$	8,751.0

		Year Ended December 31, 2018
	Revenue recognition timing	Americas		EMEA		APAC		Total
Property, facilities and project management	Over time	$	3,369.6	$	371.1	$	1,136.8	$	4,877.5
Leasing	At a point in time	1,487.5		266.1		174.1		1,927.7
Capital markets	At a point in time	702.4		173.6		86.7		962.7
Valuation and other	At a point in time or over time	165.2		189.0		97.8		452.0
Total revenue		$	5,724.7	$	999.8	$	1,495.4	$	8,219.9

		Year Ended December 31, 2017
	Revenue recognition timing	Americas		EMEA		APAC		Total
Property, facilities and project management	Over time	$	2,650.3	$	278.6	$	1,172.2	$	4,101.1
Leasing	At a point in time	1,229.3		256.9		149.7		1,635.9
Capital markets	At a point in time	531.4		153.9		55.8		741.1
Valuation and other	At a point in time or over time	189.2		173.9		82.7		445.8
Total revenue		$	4,600.2	$	863.3	$	1,460.4	$	6,923.9

Schedule of New Accounting Pronouncements and Changes in Accounting Principles

	Year Ended December 31, 2018
Statement of Operations	Balance Without Adoption of Topic 606			Adoption Impact		As Reported
Revenue	$	7,787.1		$	432.8	$	8,219.9
Cost of services	6,220.6			421.8		6,642.4
Total costs and expenses	7,785.5			421.8		8,207.3
Operating income	1.6			11.0		12.6
Loss before income taxes	(221.8		)	11.0		(210.8		)
Benefit for income taxes	(29.6		)	4.6		(25.0		)
Net loss	$	(192.2	)	$	6.4	$	(185.8	)

	Balance as of December 31, 2018
Balance Sheet	Balance Without Adoption of Topic 606			Adoption Impact			As Reported
Trade and other receivables	$	1,410.7		$	52.8		$	1,463.5
Prepaid expenses and other current assets	182.8			160.6			343.4
Total current assets	2,529.9			213.4			2,743.3
Other non-current assets	463.7			25.8			489.5
Total assets	6,306.8			239.2			6,546.0
Accounts payable and accrued expenses	994.9			52.8			1,047.7
Accrued compensation	709.8			108.1			817.9
Total current liabilities	1,877.8			160.9			2,038.7
Deferred tax liabilities	119.3			17.1			136.4
Other non-current liabilities	347.7			18.9			366.6
Total liabilities	4,989.0			196.9			5,185.9
Accumulated deficit	(1,341.2		)	42.8			(1,298.4		)
Accumulated other comprehensive loss	(153.9		)	(0.5		)	(154.4		)
Total equity	1,317.8			42.3			1,360.1
Total liabilities and shareholders’ equity	6,306.8			239.2			6,546.0