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Limited partnership units exchange ratio.

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Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Granted

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares authorized for issuance under share-based payment arrangement.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of shares issued under share-based payment arrangement.

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Number of shares purchased for issuance under share-based payment arrangement.

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Intrinsic value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Number of options vested.

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Compensation - Narrative (Details) $ in Thousands		12 Months Ended
Compensation - Narrative (Details) $ in Thousands	Oct. 18, 2024 shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares	Oct. 23, 2024	Oct. 17, 2024 shares	Sep. 23, 2024	Dec. 13, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio		0.4545			0.9257		0.9248
Unrecognized compensation expense \| $		$ 65,100
Compensation expense (benefit) \| $		$ (700)	$ 0	$ (4,700)
Common stock, conversion for each restricted stock unit settled (in shares)		1
Non Distribution Earning Units
Share-based Compensation Arrangement by Share-based Payment Award
Unit granted during period (in shares)		12,300,000	24,300,000	14,100,000
Number of shares vested and converted (in shares)		10,400,000	11,600,000	11,800,000
Newmark Holdings, L.P.
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio		0.4545
Newmark Holdings Units
Share-based Compensation Arrangement by Share-based Payment Award
Compensation expense (benefit) \| $		$ 163,744	$ 124,805	$ 122,437
Newmark Holdings Units \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period		7 years
Shares purchased for award (in shares)		4,400,000
Fair value of non-vested \| $		$ 66,000
Unrecognized compensation expense \| $		$ 32,800
Cost not yet recognized, period for recognition		2 years
Newmark Holdings Units \| Non Distribution Earning Units \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Shares purchased for award (in shares)		2,800,000
Maximum \| Newmark Holdings Units \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period		7 years
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio								1
Class A Common Stock \| Newmark Holdings Units
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio		0.9279
Newmark Equity Plan \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares authorized to be delivered pursuant to awards granted (in shares)						500,000,000		400,000,000
Additional share authorized (in shares)	100,000,000
Shares registered to be delivered pursuant to awards granted (in shares)		500,000,000
Shares purchased for award (in shares)		110,400,000
Shares available for future awards (in shares)		389,600,000