Limited Partnership Interests in Newmark Holdings (Details)	3 Months Ended
Mar. 31, 2026 installment
Related Party Transaction [Line Items]
Number of installments	4
Newmark Holdings
Related Party Transaction [Line Items]
Percentage of preferred partnership units awarded	0.6875%
Percentage of preferred partnership units awarded per calendar year	2.75%
BGC Holdings
Related Party Transaction [Line Items]
Percentage of preferred partnership units awarded	0.6875%
Percentage of preferred partnership units awarded per calendar year	2.75%

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