Description Of Business [Line Items]

No definition available.

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- Definition

Number institutional clients.

+ References

No definition available.

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- Definition

Shares purchased in tender offer.

+ References

No definition available.

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- Definition

Subsidiary Ownership Percentage

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No definition available.

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- Definition

Tendered shares owned by parent.

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No definition available.

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- Definition

Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

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No definition available.

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- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 30

-Article 5

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

No definition available.

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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- Definition

Number of new stock issued during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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-Publisher FASB

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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- Definition

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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- Definition

Amount to be paid per share that is classified as temporary equity by entity upon redemption. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 1

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-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (27)

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Organization and Basis of Presentation - Additional Information (Detail) $ / shares in Units, $ in Thousands				6 Months Ended	12 Months Ended
	Apr. 29, 2015 USD ($) $ / shares shares	Apr. 28, 2015 USD ($) $ / shares shares	Feb. 26, 2015 Clients $ / shares shares	Jun. 30, 2015 USD ($) Segments	Dec. 31, 2014 USD ($)
Description Of Business [Line Items]
Number of servicing segments \| Segments				2
Tendered shares owned \| shares			17,100,000
Stock issued during period, value, new issues \| $				$ 485	$ 361
GFI Group Inc. [Member]
Description Of Business [Line Items]
Business acquisition date				Feb. 26, 2015
Common stock, par value			$ 6.10
Tendered shares purchased \| shares			54,300,000
Percentage of outstanding common stock owned by parent	67.00%	67.00%	56.00%	67.00%
Number of institutional clients \| Clients			2,500
Stock issued during period, shares, new issues \| shares	43,000,000	43,000,000
Closing price per share	$ 5.81	$ 5.81
Stock issued during period, value, new issues \| $	$ 250,000	$ 250,000
Senior Notes maturity date				Jun. 19, 2018
Debt instrument, description of reference rate				LIBOR
Debt instrument, basis point	2.00%	2.00%
GFI's noncontrolling interest redeemable price per share	$ 6.10
Common Stock [Member] \| GFI Group Inc. [Member]
Description Of Business [Line Items]
Common stock, par value			$ 0.01