Restructuring Liability (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2020
Restructuring Reserve [Roll Forward]
Restructuring liability as of January 1, 2020	$ 31.9
Restructuring charges	21.2
Cash paid	(25.3)
Foreign currency translation adjustments and other	(1.1)
Restructuring liability as of March 31, 2020	26.7
Current portion		$ 20.1
Noncurrent portion		6.6
Total	26.7	26.7
Employee severance and termination
Restructuring Reserve [Roll Forward]
Restructuring liability as of January 1, 2020	19.1
Restructuring charges	19.8
Cash paid	(21.7)
Foreign currency translation adjustments and other	(0.5)
Restructuring liability as of March 31, 2020	16.7
Current portion		15.3
Noncurrent portion		1.4
Total	16.7	16.7
Employee severance and termination \| U.K./Ireland
Restructuring Reserve [Roll Forward]
Restructuring charges	12.7
Employee severance and termination \| Switzerland
Restructuring Reserve [Roll Forward]
Restructuring charges	3.0
Office closures
Restructuring Reserve [Roll Forward]
Restructuring liability as of January 1, 2020	2.2
Restructuring charges	0.4
Cash paid	(0.3)
Foreign currency translation adjustments and other	(0.1)
Restructuring liability as of March 31, 2020	2.2
Current portion		1.9
Noncurrent portion		0.3
Total	2.2	2.2
Contract termination
Restructuring Reserve [Roll Forward]
Restructuring liability as of January 1, 2020	10.6
Restructuring charges	1.0
Cash paid	(3.3)
Foreign currency translation adjustments and other	(0.5)
Restructuring liability as of March 31, 2020	7.8
Current portion		2.9
Noncurrent portion		4.9
Total	7.8	$ 7.8
Central and Corporate \| Employee severance and termination
Restructuring Reserve [Roll Forward]
Restructuring charges	$ 3.8

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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Carrying amount as of the balance sheet date of known and estimated obligations associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, which are expected to be paid in the next twelve months or in the normal operating cycle if longer. Costs of such activities include those for one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, relocating employees, and costs associated with an ongoing benefit arrangement, but excludes costs associated with the retirement of a long-lived asset.

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Amount of foreign currency translation gain (loss) which decreases (increases) the restructuring reserve.

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