Business Combinations, Goodwill by Segment (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020
BUSINESS COMBINATIONS, GOODWILL AND OTHER INTANGIBLE ASSETS [Abstract]
Finite-Lived Intangible Assets, Net	$ 620.0
Identifiable intangibles with indefinite useful lives	52.5
Goodwill [Line Items]
Servicing Asset at Amortized Cost, Other than Temporary Impairments	7.6	$ 9.3
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(11.7)	(0.7)
Goodwill, Translation Adjustments	(7.9)	(46.6)
Goodwill	4,205.1	4,120.9
Goodwill	4,224.7	4,168.2
Investment Management [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	0.0	0.0
Goodwill, Translation Adjustments	0.0	(1.0)
Goodwill	57.8	56.1
Goodwill	57.8	57.1
Americas [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(11.0)	0.0
Goodwill, Translation Adjustments	1.0	(1.7)
Goodwill	2,868.0	2,875.9
Goodwill	2,878.0	2,877.6
EMEA [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	(0.7)	(0.7)
Goodwill, Translation Adjustments	(4.5)	(41.4)
Goodwill	954.5	873.8
Goodwill	959.7	915.9
Asia Pacific [Member]
Goodwill [Roll Forward]
Goodwill, Written off Related to Sale of Business Unit	0.0	0.0
Goodwill, Translation Adjustments	(4.4)	(2.5)
Goodwill	324.8	315.1
Goodwill	$ 329.2	$ 317.6

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

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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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
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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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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

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

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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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- 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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