Compensation - Grant of Conversion Rights to Newmark Employees (Details) - Limited Partnership Units - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award
Notional value	$ 1,258	$ 8,189
Estimated fair value of limited partnership units	$ 1,133	$ 8,065

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details