Other consideration in business acquisition associated with payments related to historical compensation.

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

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- Details

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Business Combinations - Narrative (Details) - Legg Mason [Member] - USD ($) $ in Millions		3 Months Ended	6 Months Ended
	Jul. 31, 2020	Mar. 31, 2021	Mar. 31, 2021
Business Acquisition [Line Items]
Purchase consideration in cash	$ 4,500.0
Business Combination Other Consideration Historical Compensation	$ 200.0
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 762.2	$ 1,500.8
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		167.7	291.4
General, administrative and other expense [Member]
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs			6.7
Compensation and Benefits [Member]
Business Acquisition [Line Items]
Business Combination, Integration Related Costs		$ 5.6	$ 13.0