Limited Partnership Interests in Newmark Holdings and BGC Holdings (Details) shares in Millions	3 Months Ended
Mar. 31, 2024 shares	Dec. 13, 2017
Related Party Transaction
Limited partnership units exchange ratio	0.4545
Payout period for post-termination awards	4 years
Percentage to preferred units	0.6875%
Percentage to preferred units per calendar year	2.75%
Non Distribution Earning Units
Related Party Transaction
Award vesting period	7 years
Class A Common Stock
Related Party Transaction
Limited partnership units exchange ratio		1
NEWMARK Group Inc \| Class A Common Stock
Related Party Transaction
Limited partnership units exchange ratio	0.9255
NEWMARK Group Inc \| Class B Common Stock
Related Party Transaction
Exchangeable preferred limited partnership units (in shares)	24.9

Limited partnership units exchange ratio.

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Other Ownership Interests, Units Exchangeable

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Percentage of profits allocated to preferred partnership units.

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Percentage Of Profits Allocated To Preferred Partnership Units, Annual Percentage Rate

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Post termination award payout period.

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- Definition

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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