Compensation - Grant of Conversion Rights to Newmark Employees (Details) - Limited Partnership Units - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Notional value	$ 12,836	$ 12,836
Estimated fair value of limited partnership units	$ 12,558	$ 12,558

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