Commitments and Contingencies - Schedule of limited partners' callable commitments (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	$ 355.5	$ 289.3
Real Estate Funds
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	145.2	201.0
Real Estate Funds | Veritas Trophy VI, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	0.0	10.0
Real Estate Funds | JCR Capital - REA Preferred Equity Parallel Fund
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	11.5	24.8
Real Estate Funds | Silverpeak NRE FundCo 3 LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	48.6	51.5
Real Estate Funds | Townsend Group Value-Add Fund
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	49.7	57.2
Real Estate Funds | Silverpeak NRE FundCo LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	5.2	26.1
Real Estate Funds | SP V - II, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	7.5	8.7
Real Estate Funds | Silverpeak NRE FundCo 2 LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	22.7	22.7
Loans Receivable
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	55.2	88.3
Loans Receivable | Colony New England Hotel Portfolio Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	3.6	3.6
Loans Receivable | Colony New England Hotel Portfolio Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	1.2	1.2
Loans Receivable | Exo Apartments Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	5.1	5.1
Loans Receivable | Project Sonic Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	1.9	2.0
Loans Receivable | Project Sonic Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	0.6	0.7
Loans Receivable | Spring House Innovation Park Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	0.0	17.8
Loans Receivable | Spring House Innovation Park Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	0.0	5.9
Loans Receivable | One Biscayne Tower Senior Loan
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	26.8	31.8
Loans Receivable | One Biscayne Tower Mezzanine
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	8.9	10.6
Loans Receivable | MRA Hub 34 Holding, LLC
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	1.5	1.5
Loans Receivable | The Reserve at Chino Hills
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	0.9	3.3
Loans Receivable | 735 Watkins Mill
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	4.7	4.8
Real Estate Operating Business
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	155.1	0.0
Real Estate Operating Business | DigitalBridge Zeus Partners, LP
Limited Partners' Capital Account [Line Items]
TOTAL COMMITMENTS	$ 155.1	$ 0.0