Exchangeable Partnership Units

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- Definition

Limited partnership units exchange ratio.

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- Definition

Share-based compensation arrangement by share-based payment award, number of shares registered.

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- Definition

Share based compensation arrangement by share based payment award units redeemed.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for deferred compensation arrangements. Represents currently earned compensation under cash arrangements (such as a profit-sharing plan, rabbi trust, and employee contract--excluding equity-based arrangements) that is not actually paid until a later date.

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No definition available.

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- Definition

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

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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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- Definition

The number of limited partner units outstanding.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

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

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- Definition

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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- Definition

Number of shares issued under share-based payment arrangement.

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Compensation - Additional Information (Detail) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) shares	Jun. 30, 2019 USD ($) shares	Jun. 30, 2020 USD ($) shares	Jun. 30, 2019 USD ($) shares	Dec. 31, 2019 USD ($) shares	Dec. 31, 2018 shares	Dec. 13, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award
Shares available for future awards (in shares)	372,500,000		372,500,000
Number of units redeemed (in shares)	64,764	257,091	356,485	346,091
Unrecognized compensation expense related to unvested RSUs \| $	$ 80,500		$ 80,500
Deferred cash compensation expense recognized \| $	100	$ 200	200	$ 400
Liability for deferred cash compensation awards \| $	$ 1,100		$ 1,100		$ 1,500
Newmark Holdings, L.P.
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio (in percentage)	0.4545		0.4545
Newmark Holdings, L.P. \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units outstanding (in shares)	10,211,762		10,211,762		4,683,571	219,887
BGC Holdings, L.P.
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units outstanding (in shares)	55,847,313		55,847,313		56,053,701	61,870,969
BGC Holdings, L.P. \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units outstanding (in shares)	9,600,000		9,600,000		9,500,000
Exchangeable partnership units (in shares)	5,000,000.0		5,000,000.0		2,900,000
NEWMARK Group Inc Parent
Share-based Compensation Arrangement by Share-based Payment Award
Limited partners capital account units held by BGC (in shares)	17,820,912		17,820,912		17,097,639
Limited partnership units outstanding (in shares)	64,932,884		64,932,884		60,800,852	44,733,487
Number of units redeemed (in shares)	26,212	24,466	168,653	54,466
Unrecognized compensation expense related to unvested RSUs \| $	$ 100		$ 100
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units outstanding (in shares)	5,300,000		5,300,000		5,300,000
Exchangeable partnership units (in shares)	2,200,000		2,200,000		1,400,000
NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Income allocated to limited partnership units \| $	$ 1,104	$ 11,601	$ 1,653	$ 17,915
Maximum \| Newmark Holdings, L.P. \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period			8 years
Maximum \| NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period			7 years
Minimum \| Newmark Holdings, L.P. \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period			2 years
Minimum \| NEWMARK Group Inc Parent \| Limited Partnership Units
Share-based Compensation Arrangement by Share-based Payment Award
Award vesting period			3 years
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award
Limited partnership units exchange ratio (in percentage)	0.9366		0.9366				1
Newmark Equity Plan \| Class A Common Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Shares authorized to be delivered pursuant to awards granted (in shares)							400,000,000.0
Shares registered to be delivered pursuant to awards granted (in shares)							65,000,000.0
Non Distribution Earning Units
Share-based Compensation Arrangement by Share-based Payment Award
Unit granted during period (in shares)	1,400,000		6,300,000
Award vesting period			4 years
Executives And Non Executives Employees
Share-based Compensation Arrangement by Share-based Payment Award
Limited partners capital account units held by BGC (in shares)	27,500,000		27,500,000