Business Combinations, Goodwill by Segment (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	$ 286.1
Identifiable intangibles with indefinite useful lives	50.0
Goodwill [Line Items]
Servicing Asset at Amortized Cost, Other than Temporary Impairments	3.0	$ 6.5
Goodwill [Roll Forward]
Goodwill	2,697.8	2,709.3
Goodwill Additions, net of adjustments	40.2	8.9
Goodwill, Translation Adjustments	(7.3)	(35.3)
Goodwill	2,730.7	2,682.9
Investment Management [Member]
Goodwill [Roll Forward]
Goodwill	22.2	16.5
Goodwill Additions, net of adjustments	35.4	0.0
Goodwill, Translation Adjustments	(1.0)	(0.3)
Goodwill	56.6	16.2
Americas [Member] \| Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill	1,452.0	1,412.2
Goodwill Additions, net of adjustments	3.2	6.9
Goodwill, Translation Adjustments	1.2	(0.8)
Goodwill	1,456.4	1,418.3
EMEA [Member] \| Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill	906.8	957.6
Goodwill Additions, net of adjustments	1.6	0.1
Goodwill, Translation Adjustments	(8.0)	(27.7)
Goodwill	900.4	930.0
Asia Pacific [Member] \| Reportable Subsegments [Member]
Goodwill [Roll Forward]
Goodwill	316.8	323.0
Goodwill Additions, net of adjustments	0.0	1.9
Goodwill, Translation Adjustments	0.5	(6.5)
Goodwill	317.3	$ 318.4
Other Intangible Assets [Member]
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	89.7
Mortgage servicing rights [Member]
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	$ 196.4

-- None. No documentation exists for this element. --

No definition available.

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- Definition

The aggregate amount of goodwill acquired in the period and allocated to the reportable segment. The value is stated at fair value based on the purchase price allocation. Also includes purchase price allocation adjustment for allocations not yet complete at the prior year end.

+ References

No definition available.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

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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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

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-Publisher FASB
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- Definition

Amount of other-than-temporary impairment (OTTI) applied to contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

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-Publisher FASB
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-SubTopic 50
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