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Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2019
Commitments and Contingencies
Co-investment commitments in partnership		$ 146.6
Noncontrolling interest, sell of ownership percentage		5.00%
Equity Method Investee
Commitments and Contingencies
Contingent liability		$ 152.5
Equity Method Investee | Non-US
Commitments and Contingencies
Ownership percentage held by minority interest in affiliate to the Company		19.00%
Equity Method Investee | Subsequent Event | Non-US | Scenario, Forecast
Commitments and Contingencies
Payments to noncontrolling interest for additional equity interest in affiliate	$ 25.7

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The amount that the entity agreed to co-invest in certain investment partnerships where the entity serves as the general partner.

+ References

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- Definition

Noncontrolling Interest, Notification of Possible Sale of Noncontrolling Interest, Percentage

+ References

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

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- Definition

Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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