Variable Interest Entities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Investments (includes balances reported at fair value of $119.5 and $124.8)	$ 303.8	$ 321.4
Consolidated VIEs
Assets
Investments (includes balances reported at fair value of $119.5 and $124.8)	119.5	124.8
Other assets of consolidated Funds	85.7	19.8
Total Assets	205.2	144.6
Liabilities
Liabilities of consolidated Funds	6.2	14.9
Total Liabilities	6.2	14.9
Unconsolidated VIEs
Unconsolidated VIE [Abstract]
Unconsolidated VIE assets	6,625.5	4,814.9
Unconsolidated VIE liabilities	4,320.6	2,115.1
Equity interests on the Consolidated Balance Sheets	17.5	22.5
Maximum risk of loss	$ 23.9	$ 31.0

Unconsolidated VIE [Abstract]

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- Definition

Represents the equity interests in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the unconsolidated Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

No definition available.

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of assets classified as other.

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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Amount of liabilities classified as other.

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- Definition

The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.

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The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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- Definition

Carrying amount of the assets in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

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- Definition

Carrying amount of the liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the Variable Interest Entity (VIE), where the reporting entity is not the VIE's primary beneficiary.

+ References

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