Compensation - Compensation Expense Related to Limited Partnership Units and Restricted Stock Units (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	$ 28,898	$ 241,585	$ 37,881	$ 248,196
Equity-based compensation and allocations of net income to limited partnership units and FPUs			58,886	296,073
Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	(2,023)	181,994	(2,023)	176,601
NEWMARK Group Inc Parent
Share-based Compensation Arrangement by Share-based Payment Award
Equity-based compensation and allocations of net income to limited partnership units and FPUs	41,988	267,532	58,886	281,780
NEWMARK Group Inc Parent \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units amortization	5,566	4,449	10,061	7,446
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	26,875	242,324	35,858	243,542
Allocations of net income to limited partnership units and FPUs	7,787	14,293	7,933	24,926
Limited partnership units amortization	$ 1,760	$ 6,466	$ 5,034	$ 5,866

Common Stock, Exchangeability Granted, Issued, Expense

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- Definition

Equity Based Compensation And Allocation Of Net Income To Limited Partnership Units And FPUs

+ References

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- Definition

Amount of equity impact of cash distribution declared to unit-holder of limited partnership (LP).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187085-122770

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- Definition

Amount of expense for employee benefit and equity-based compensation.

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- Definition

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