v3.26.3
Assets and Liabilities Measured at Fair Value on a Recurring Basis - Schedule of Reconciliation of Assets and Liabilities Measured at Fair Value on Recurring Basis, Unobservable Inputs (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Total realized and unrealized gains (losses) included in changes in net assets $ 628.5 $ (12.6) $ 847.5 $ 23.9
Loans Payable        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance (729.4) (933.3) (830.3) (1,585.5)
Total realized and unrealized gains (losses) included in changes in net assets 3.2 7.3 7.2 72.3
Purchases 0.0 (0.4) 0.0 (0.4)
Sales 0.0 0.0 0.0 0.0
Settlements 134.5 92.3 231.4 679.5
Ending balance (591.7) (834.1) (591.7) (834.1)
Line of Credit        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance (250.0) (219.0) (160.0) 0.0
Total realized and unrealized gains (losses) included in changes in net assets 0.0 0.0 0.0 0.0
Purchases (452.0) (357.0) (542.0) (576.0)
Sales 0.0 0.0 0.0 0.0
Settlements 400.0 0.0 400.0 0.0
Ending balance (302.0) (576.0) (302.0) (576.0)
Real Estate Properties        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 15,978.2 15,451.0 15,975.4 15,607.0
Total realized and unrealized gains (losses) included in changes in net assets 49.7 17.6 (50.7) (40.0)
Purchases 607.2 431.7 1,076.6 1,010.6
Sales (460.1) (46.0) (826.3) (723.3)
Settlements 0.0 0.0 0.0 0.0
Ending balance 16,175.0 15,854.3 16,175.0 15,854.3
Real Estate Joint Ventures        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 5,206.6 5,220.8 5,098.8 5,381.4
Total realized and unrealized gains (losses) included in changes in net assets 48.2 42.2 114.5 73.7
Purchases 88.3 120.6 158.3 211.9
Sales 0.0 0.0 0.0 0.0
Settlements (25.1) (0.8) (53.6) (284.2)
Ending balance 5,318.0 5,382.8 5,318.0 5,382.8
Real Estate Operating Business        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 1,245.1 1,033.1 1,072.6 931.8
Total realized and unrealized gains (losses) included in changes in net assets 597.4 53.0 768.3 25.0
Purchases 0.0 0.0 1.6 129.3
Sales 0.0 0.0 0.0 0.0
Settlements 0.0 0.0 0.0 0.0
Ending balance 1,842.5 1,086.1 1,842.5 1,086.1
Loans Receivable        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 474.0 849.1 690.4 877.8
Total realized and unrealized gains (losses) included in changes in net assets (1.6) (29.6) (7.8) (36.2)
Purchases 4.9 4.9 10.3 11.2
Sales 0.0 0.0 0.0 0.0
Settlements (158.8) (135.5) (374.4) (163.9)
Ending balance 318.5 688.9 318.5 688.9
Total Level 3 Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 22,903.9 22,554.0 22,837.2 22,798.0
Total realized and unrealized gains (losses) included in changes in net assets 693.7 83.2 824.3 22.5
Purchases 700.4 557.2 1,246.8 1,363.0
Sales (460.1) (46.0) (826.3) (723.3)
Settlements (183.9) (136.3) (428.0) (448.1)
Ending balance $ 23,654.0 $ 23,012.1 $ 23,654.0 $ 23,012.1