Acquisitions Acquisitions (Details) (G.X. Clarke (INTL FCStone Partners) [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2014
G.X. Clarke (INTL FCStone Partners) [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net	$ 26.0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	1.5
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	$ 1.5

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (c)(3)

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

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-Section 50

-Paragraph 1

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