Share based compensation, unvested restricted awards outstanding unamortized.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Expiration Period

+ References

No definition available.

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- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

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- Definition

Number of non-option equity instruments exercised by participants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

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.

+ References

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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Stock-Based Compensation - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares)	2,000,000.0	0	2,000,000.0	0
Number of stock options exercised (in shares)	1,800	0	1,800	0
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Accelerated amortization expense		$ 28.8		$ 28.8
RSUs \| Employee Compensation and Benefits
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Accelerated amortization expense		$ 28.8		$ 28.8
Restricted awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation related to restricted awards outstanding	$ 5.2		$ 5.2
Cost of unvested awards expected to be recognized over a weighted average life, years			1 year 9 months 23 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			3 years
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period			5 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award expiration period			10 years
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SARs granted (in shares)	0	0	0	0
Number of SARs exercised during period (in shares)	0	0	0	0
Unamortized compensation costs	$ 0.7		$ 0.7
Award expiration period			1 year 8 months 29 days
Incentive units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred compensation payable	$ 2.6		$ 2.6		$ 2.4
KCG Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grant (in shares)		25,100,000		25,100,000
Number of shares available for grant		13,100,000		13,100,000
KCG Plan \| Time-based awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
KCG Plan \| Performance-based awards \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				1 year