Related Party Transactions - Cantor Rights to Purchase Cantor Units from Newmark Holdings (Details)	Jun. 30, 2023 USD ($) shares	Apr. 16, 2023 USD ($) shares	Mar. 31, 2024 shares	Nov. 06, 2018	Dec. 13, 2017
Related Party Transaction
Limited partnership units exchange ratio			0.4545
Related Party | Founding Partner Exchange Units
Related Party Transaction
Warrants and rights outstanding (in shares)			53,168
Founding partner interest | Related Party
Related Party Transaction
Issuance of Class A common stock for Newmark RSUs (in shares)	74,026	309,631
Proceeds from the sale of limited partnership interests | $	$ 310,976	$ 1,282,265
Limited partner interest | Related Party
Related Party Transaction
Issuance of Class A common stock for Newmark RSUs (in shares)		38,989
Proceeds from the sale of limited partnership interests | $		$ 166,364
Common Stock
Related Party Transaction
Limited partnership units exchange ratio				1
Class A Common Stock
Related Party Transaction
Limited partnership units exchange ratio					1
Class A Common Stock | NEWMARK Group Inc
Related Party Transaction
Limited partnership units exchange ratio			0.9255