Deferred compensation arrangement with individual compensation expense not yet recognized.

No definition available.

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- Definition

Deferred compensation arrangement with individual compensation expense not yet recognized period for recognition.

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No definition available.

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- Definition

Estimated fair value of deferred compensation awards.

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No definition available.

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- Definition

Estimated fair value of limited partnership units held by executives and non-executive employees, awarded in lieu of cash compensation for salaries, commissions and/or discretionary or guaranteed bonuses.

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- Definition

Estimated fair value of limited partnership units and restricted stock units.

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No definition available.

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- Definition

Limited Partnership Interest, Conversion Ratio

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- Definition

Limited partnership interests exchange ratio, subject to adjustment.

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- Definition

Notional value of limited partnership units with post termination pay out amount.

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No definition available.

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- Definition

Number of limited partnership units exchangeable into shares.

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number Of Restricted Stock Unit Settled Per Common Stock

+ References

No definition available.

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- Definition

Period over which the sale or transferability of an the equity-based payment award is restricted, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Restricted shares that were previously issued and then had their restriction released during the period.

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No definition available.

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- Definition

Value of shares withheld for tax, related to share-based compensation.

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No definition available.

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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

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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

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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

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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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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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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Number of shares related to Restricted Stock Award forfeited during the period.

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Compensation - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) shares	Nov. 22, 2021 shares	Nov. 21, 2021 shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate number of shares grant of future awards (in shares)	164,500,000
Limited partnership interest, conversion ratio	1
Number of share-equivalent limited partnership units exchangeable into shares (in shares)	1,300,000	3,500,000
Number of restricted stock unit settled per common stock (in shares)	1
Aggregate estimated fair value of limited partnership units and restricted stock units \| $	$ 8,900	$ 9,400
Aggregate estimated fair value of the deferred compensation awards \| $	$ 21,700	$ 23,600
Shares, forfeited (in shares)	140,000	0
Number of shares released the restrictions (in shares)	1,100,000	700,000
Deferred cash compensation expense recognized \| $	$ 347	$ 630	$ 5,879
Deferred cash compensation expense not yet recognized \| $	$ 100
Deferred compensation expense, expected period of recognition	2 years 3 months 10 days
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested \| $	$ 35,600
Unrecognized compensation expense related to unvested recognized period	2 years 3 months 7 days
Limited partnership units outstanding (in shares)	11,034,000	8,960,000	4,478,000			929,000
Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Limited partnership units outstanding (in shares)	2,600,000	3,700,000
Minimum \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares saleable period	5 years
Maximum \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares saleable period	10 years
LPUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested \| $	$ 100,900
Unrecognized compensation expense related to unvested recognized period	2 years 1 month 6 days
Limited partnership units outstanding (in shares)	112,115,000	137,652,000	102,407,000			79,729,000
LPUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares, restriction period	2 years
LPUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares, restriction period	5 years
Newmark
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares released the restrictions (in shares)	500,000	300,000
Newmark \| Restricted Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Limited partnership units outstanding (in shares)	1,200,000	1,700,000
Newmark \| LPUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Limited partnership units outstanding (in shares)	11,051,000	13,202,000	14,607,000			22,113,000
Newmark \| LPUs \| REUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Notional value with post-termination pay-out amount \| $	$ 800	$ 800
Aggregate estimated fair value of limited partnership units \| $	$ 400	$ 300
BGC Holdings \| LPUs \| REUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of unvested limited partnership units with post-termination pay-out (in shares)	1,300,000	1,300,000
Notional value with post-termination pay-out amount \| $	$ 12,400	$ 12,700
Aggregate estimated fair value of limited partnership units \| $	$ 7,400	$ 7,500
Number of outstanding limited partnership units, unvested (in shares)	100,000	100,000
GFI Group Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred cash compensation expense recognized \| $	$ 300	$ 800	$ 5,900
Liability for deferred cash compensation awards \| $	$ 800	$ 1,500
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of share-equivalent limited partnership units exchangeable into shares (in shares)	400,000	500,000
Shares, forfeited (in shares)	140,000	0
Class A Common Stock \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of shares withheld \| $	$ 4,400	$ 1,900
Class A Common Stock \| Newmark
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Limited partnership interests exchange Ratio	94.44%
Equity Plan \| Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to be delivered pursuant to awards granted (in shares)				500,000,000	400,000,000