v3.26.1
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 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 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 $ 195.2 $ 10.2 $ 219.0 $ 36.5
Loans Payable        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance (809.8) (1,355.8) (830.3) (1,585.5)
Total realized and unrealized gains (losses) included in changes in net assets (5.9) 60.7 4.0 65.0
Purchases 0.0 0.0 0.0 0.0
Sales 0.0 0.0 0.0 0.0
Settlements 86.3 361.8 96.9 587.2
Ending balance (729.4) (933.3) (729.4) (933.3)
Line of Credit        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance (160.0) 0.0 (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 (90.0) (219.0) (90.0) (219.0)
Sales 0.0 0.0 0.0 0.0
Settlements 0.0 0.0 0.0 0.0
Ending balance (250.0) (219.0) (250.0) (219.0)
Real Estate Properties        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 16,023.0 15,546.3 15,975.4 15,607.0
Total realized and unrealized gains (losses) included in changes in net assets (37.0) 18.6 (100.4) (57.6)
Purchases 170.2 392.6 469.3 578.9
Sales (178.0) (506.5) (366.1) (677.3)
Settlements 0.0 0.0 0.0 0.0
Ending balance 15,978.2 15,451.0 15,978.2 15,451.0
Real Estate Joint Ventures        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 5,136.9 5,234.5 5,098.8 5,381.4
Total realized and unrealized gains (losses) included in changes in net assets 67.4 (59.1) 66.3 31.5
Purchases 11.6 47.6 70.0 91.3
Sales 0.0 0.0 0.0 0.0
Settlements (9.3) (2.2) (28.5) (283.4)
Ending balance 5,206.6 5,220.8 5,206.6 5,220.8
Real Estate Operating Business        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 1,082.0 1,058.8 1,072.6 931.8
Total realized and unrealized gains (losses) included in changes in net assets 161.5 (27.8) 170.9 (28.0)
Purchases 1.6 2.1 1.6 129.3
Sales 0.0 0.0 0.0 0.0
Settlements 0.0 0.0 0.0 0.0
Ending balance 1,245.1 1,033.1 1,245.1 1,033.1
Loans Receivable        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 564.3 852.6 690.4 877.8
Total realized and unrealized gains (losses) included in changes in net assets (5.6) (7.4) (6.2) (6.6)
Purchases 2.2 4.2 5.5 6.3
Sales 0.0 0.0 0.0 0.0
Settlements (86.9) (0.3) (215.7) (28.4)
Ending balance 474.0 849.1 474.0 849.1
Total Level 3 Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 22,806.2 22,692.2 22,837.2 22,798.0
Total realized and unrealized gains (losses) included in changes in net assets 186.3 (75.7) 130.6 (60.7)
Purchases 185.6 446.5 546.4 805.8
Sales (178.0) (506.5) (366.1) (677.3)
Settlements (96.2) (2.5) (244.2) (311.8)
Ending balance $ 22,903.9 $ 22,554.0 $ 22,903.9 $ 22,554.0