Earn out shares receivable under common stock transaction.

No definition available.

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- Definition

Earn out shares received under common stock transaction.

+ References

No definition available.

+ Details

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- Definition

Gross revenue on earn out shares receivable per year under common stock transaction.

+ References

No definition available.

+ Details

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- Definition

Marketable securities number of shares sold.

+ References

No definition available.

+ Details

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- Definition

Period for earn out receivable under common stock transaction.

+ References

No definition available.

+ Details

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- Definition

Remaining earn out shares receivable under common stock transaction.

+ References

No definition available.

+ Details

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- Definition

Remaining Number Of Earn Out Shares Received Under Common Stock Transaction

+ References

No definition available.

+ Details

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- Definition

Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Amount of unrealized gain (loss) on investment in marketable security.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(7)(c))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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- Definition

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Marketable Securities (Details) - USD ($)		3 Months Ended	12 Months Ended
Marketable Securities (Details) - USD ($)	Jun. 28, 2013	Jun. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2020
Marketable Securities
Gain (loss) on marketable securities			$ (2,204,000)	$ 4,056,000	$ 3,256,000
Gross proceeds from sale of marketable securities			34,738,000	32,606,000	95,878,000
Unrealized (gains) loss on marketable securities			$ 5,004,000	$ 11,303,000	(1,193,000)
Common Stock
Marketable Securities
Amount recognized in connection with the earn-out including other income (loss) (in shares)			992,247	992,247
Gain (loss) on marketable securities		$ (2,200,000)		$ 4,100,000	$ 3,300,000
Number of shares sold in transaction (in shares)			343,562	350,000	1,142,247
Gross proceeds from sale of marketable securities			$ 34,700,000	$ 32,600,000	$ 95,900,000
Unrealized (gains) loss on marketable securities			5,000,000.0	11,300,000	(1,200,000)
Marketable securities			33,300,000	36,800,000
Common Stock \| Nasdaq Earn-Out
Marketable Securities
Gain (loss) on marketable securities			$ 121,900,000	$ 98,600,000	$ 85,100,000
Marketable securities						$ 121,900,000
Maximum \| Common Stock
Marketable Securities
Remaining earn-out receivable under common stock transaction (in shares)	6,945,729
Minimum \| Common Stock
Marketable Securities
Gross revenue on earn-out receivable per year under common stock transaction	$ 25,000,000.0
Nasdaq Omx
Marketable Securities
Remaining shares from earn out transaction (in shares)			250,742	343,562	600,000
BGC Partners Inc \| Common Stock
Marketable Securities
Period for earn-out receivable under common stock transaction (years)			7 years
BGC Partners Inc \| Nasdaq Omx
Marketable Securities
Period for earn-out receivable under common stock transaction (years)	15 years
BGC Partners Inc \| Nasdaq Omx \| Maximum
Marketable Securities
Earn-out shares receivable under common stock transaction (in shares)	14,883,705
BGC Partners Inc \| Nasdaq Omx \| Minimum
Marketable Securities
Gross revenue on earn-out receivable per year under common stock transaction	$ 25,000,000.0