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Investments in Real Estate Ventures, at Fair Value, Foreign Currency Translation

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Number of separate property or fund co-investments.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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

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Investments (Details) $ in Millions	3 Months Ended		6 Months Ended
Investments (Details) $ in Millions	Jun. 30, 2025 USD ($) investment	Jun. 30, 2024 USD ($)	Jun. 30, 2025 USD ($) investment	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Schedule of Equity Method Investments [Line Items]
Number of separate property or fund co-investments \| investment	50		50
Investments	$ 878.8		$ 878.8		$ 812.7
Fair Value [Abstract]
Fair value investments at beginning of the period			742.0	$ 740.8
Investments in Real Estate Ventures, at Fair Value, Additions			135.4	35.0
Investments in Real Estate Ventures, at Fair Value, Distributions			(34.2)	(11.6)
Unrealized Gain (Loss) on Investments			(54.3)	(17.3)
Investments in Real Estate Ventures, at Fair Value, Foreign Currency Translation			20.2	(10.6)
Investments previously accounted at cost that are now being accounted for at Net Asset value	24.6		24.6
Fair value investments at end of the period	833.7	$ 744.7	833.7	744.7
Equity Investments accounted for under the measurement alternative	8.0		8.0
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member]
Fair Value [Abstract]
Fair value investments at beginning of the period	311.0	369.7	330.3	367.3
Fair value investments at end of the period	293.1	367.8	293.1	367.8
Fair Value, Inputs, Level 3 [Member] \| Fair Value, Recurring [Member] \| Investments [Member]
Fair Value [Abstract]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0.0	$ 5.2	0.0	$ 8.4
Software and Technology Solutions
Schedule of Equity Method Investments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	8.1		8.1
Investments	334.7		334.7		372.8
Fair Value [Abstract]
Asset Impairment Charges			2.2
Investment Management
Schedule of Equity Method Investments [Line Items]
Guarantor Obligations, Maximum Exposure, Undiscounted	211.4		211.4
Investments	508.7		508.7		406.1
Other Investments and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures
Schedule of Equity Method Investments [Line Items]
Investments	$ 35.4		$ 35.4		$ 33.8