Compensation - Compensation Expense Related to Limited Partnership Units and Restricted Stock Units (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	$ 8,983	$ 6,611
Equity-based compensation and allocations of net income to limited partnership units and FPUs	16,899	14,296
Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	0	(5,394)
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	16,899	14,248
NEWMARK Group Inc Parent \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units amortization	4,495	2,997
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	8,983	1,218
Allocations of net income to limited partnership units and FPUs	147	10,633
Limited partnership units amortization	$ 3,274	$ (600)

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 http://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

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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