Description Of Business [Line Items]

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- Definition

Subsidiary ownership percentage.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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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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- Details

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Organization and Basis of Presentation - Additional Information (Detail) - Segment	3 Months Ended
	Mar. 31, 2017	Nov. 04, 2016	Jan. 12, 2016
Description Of Business [Line Items]
Number of servicing segments	2
Lucera [Member]
Description Of Business [Line Items]
Ownership percentage acquired		80.00%
Jersey Partners, Inc. [Member]
Description Of Business [Line Items]
Business acquisition date	Dec. 22, 2015
GFI Group Inc. [Member]
Description Of Business [Line Items]
Investment ownership percentage amount			33.00%
Percentage of outstanding common stock owned by parent			100.00%
Ownership percentage acquired			100.00%