Compensation - Compensation Expense Related to Limited Partnership Units and Restricted Stock Units (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	$ 97,031	$ 317,281	$ 36,458
Equity-based compensation and allocations of net income to limited partnership units and FPUs	138,312	356,345	130,759
Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	(4,723)	(4,563)	32,583
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	138,312	356,345	130,759
NEWMARK Group Inc Parent \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units amortization	21,807	16,795	12,565
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Issuance of common stock and exchangeability expenses	92,308	312,718	69,041
Allocations of net income to limited partnership units and FPUs	15,875	55,183	30,461
Limited partnership units amortization	$ 8,322	$ (28,351)	$ 18,692

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

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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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