Face (par) amount of debt instrument at time of issuance.

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

- 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.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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Borrowings and Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Aug. 20, 2019	Aug. 19, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Carrying value	$ 568.8			$ 393.3
Fair Value	588.6			368.3
Third party borrowings
Debt Instrument [Line Items]
Carrying value	533.8			393.3
Fair Value	553.6			368.3
Third party borrowings \| Credit Facility
Debt Instrument [Line Items]
Carrying value	140.0			0.0
Fair Value	140.0			0.0
Third party borrowings \| Senior Notes, 4.80%, due 2026
Debt Instrument [Line Items]
Carrying value	272.4			272.2
Fair Value	287.2			266.0
Third party borrowings \| Senior Notes, 5.125%, due 2031
Debt Instrument [Line Items]
Carrying value	121.4			121.1
Fair Value	126.4			102.3
Non-recourse Seed Capital Facility
Debt Instrument [Line Items]
Carrying value	35.0			0.0
Fair Value	35.0			0.0
Non-recourse Seed Capital Facility \| Credit Facility
Debt Instrument [Line Items]
Carrying value	35.0			0.0
Fair Value	$ 35.0			$ 0.0
Citibank \| Revolving credit facility \| Line of Credit
Debt Instrument [Line Items]
Maturity amount		$ 450.0	$ 350.0
Consolidated Entity Excluding Consolidated Funds \| Citibank \| Revolving credit facility \| Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 450.0