Net Gain on Disposition of Subsidiaries and Repositioning Actions, Total

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Includes, but is not limited to, one-time termination benefits, termination of an operating lease or other contract, consolidating or closing facilities, and relocating employees, and termination benefits associated with an ongoing benefit arrangement. Excludes expenses associated with special or contractual termination benefits, a discontinued operation or an asset retirement obligation.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount of other expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses 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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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.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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Dispositions of Subsidiaries and Repositioning Actions (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Severance	$ 68.4
Office lease consolidation and terminations	73.5
Asset write-offs related to disposals and other costs	7.5
Repositioning Actions	149.4
Net gain on disposition of subsidiaries	(178.4)	$ 0.0	$ (178.4)	$ 0.0
Salary and service costs
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	73.7
Net gain on disposition of subsidiaries	0.0
Net gain on disposition of subsidiaries and repositioning actions, total	73.7
Occupancy and other costs
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	73.5
Net gain on disposition of subsidiaries	0.0
Net gain on disposition of subsidiaries and repositioning actions, total	73.5
Net gain on disposition of subsidiaries
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	0.0
Net gain on disposition of subsidiaries	(178.4)
Net gain on disposition of subsidiaries and repositioning actions, total	(178.4)
Cost of services
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	147.2
Net gain on disposition of subsidiaries	(178.4)
Net gain on disposition of subsidiaries and repositioning actions, total	(31.2)
Selling, general and administrative expenses
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	2.2
Net gain on disposition of subsidiaries	0.0
Net gain on disposition of subsidiaries and repositioning actions, total	2.2
Depreciation and amortization
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	0.0
Net gain on disposition of subsidiaries	0.0
Net gain on disposition of subsidiaries and repositioning actions, total	0.0
Operating expenses
Dispositions of Subsidiaries and Repositioning Actions [Line Items]
Repositioning Actions	149.4
Net gain on disposition of subsidiaries	(178.4)
Net gain on disposition of subsidiaries and repositioning actions, total	$ (29.0)