Organization, Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Operating Partnership's Equity Interest (Details) $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($)
Fund II and Mervyns II
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating Partnership Share of Capital	28.33%
Capital Called	$ 384.1
Unfunded Commitment	$ 1.2
Equity interest held by Operating Partnership	28.33%
Preferred Return	8.00%
Total Distributions	$ 169.8
Fund III
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating Partnership Share of Capital	24.54%
Capital Called	$ 448.1
Unfunded Commitment	$ 1.9
Equity interest held by Operating Partnership	24.54%
Preferred Return	6.00%
Total Distributions	$ 601.5
Fund IV
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating Partnership Share of Capital	23.12%
Capital Called	$ 488.1
Unfunded Commitment	$ 41.9
Equity interest held by Operating Partnership	23.12%
Preferred Return	6.00%
Total Distributions	$ 193.1
Fund V
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Operating Partnership Share of Capital	20.10%
Capital Called	$ 347.9
Unfunded Commitment	$ 172.1
Equity interest held by Operating Partnership	20.10%
Preferred Return	6.00%
Total Distributions	$ 61.0