Summary of Significant Accounting Policies - Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Revenue from External Customer
Revenues	$ 678,247	$ 503,980
Management services, servicing fees and other
Revenue from External Customer
Revenues	233,120	187,751
Leasing and other commissions
Revenue from External Customer
Revenues	198,952	147,433
Investment sales
Revenue from External Customer
Revenues	152,113	101,545
Commercial mortgage origination, net
Revenue from External Customer
Revenues	$ 94,062	$ 67,251

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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+ Details