Summary of Significant Accounting Policies - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenue from External Customer
Revenues	$ 664,646	$ 788,125	$ 2,098,245	$ 1,921,977
Management services, servicing fees and other
Revenue from External Customer
Revenues			689,183	651,729
Leasing and other commissions
Revenue from External Customer
Revenues			631,681	563,311
Investment sales
Revenue from External Customer
Revenues			492,898	452,565
Commercial mortgage origination, net
Revenue from External Customer
Revenues			$ 284,483	$ 254,372