Compensation - Compensation Expense Related to Limited Partnership Units and Restricted Stock Units (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	$ 33,330	$ 14,321	$ 71,211	$ 302,764
Equity-based compensation and allocations of net income to limited partnership units and FPUs			102,974	315,742
Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	0	93	(2,023)	(4,562)
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	44,088	33,963	102,974	315,743
NEWMARK Group Inc Parent \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units amortization	5,702	4,059	15,764	11,505
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	33,330	14,414	69,188	298,202
Allocations of net income to limited partnership units and FPUs	4,875	13,167	12,808	38,092
Limited partnership units amortization	$ 181	$ 2,323	$ 5,214	$ (32,056)

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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