Share-based Compensation by Share-based Payment Award, Initial Contractual Term

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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-Publisher FASB
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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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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.

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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No definition available.

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- Definition

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

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-Based Compensation and Employee Ownership Plans Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares		56,519
Share Price	$ 13.34	$ 13.65
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number		191,962
Equity Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-compensation expense recognized in connection with compensation plan	$ 37.0	$ 28.4	$ 26.0
Tax benefit of stock-compensation expense recognized in connection with compensation plan	$ 9.7	$ 7.7	$ 11.4
Equity Plans \| Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, initial term	7 years
Equity Plans \| Employee Stock Option \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation award, vesting period	2 years
Equity Plans \| Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation award, vesting period	5 years
Equity Plans \| Restricted Shares and Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 56.1
Vested, shares	1,961,824	2,036,366
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	5,962,295	5,579,293	5,717,932
Equity Plans \| Restricted Stock \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation award, vesting period	2 years
Equity Plans \| Restricted Stock \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation award, vesting period	5 years
Equity Plans \| Restricted Stock Units (RSUs) \| Non-employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares	88,504
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	253,772
Equity Plans \| Stock Appreciation Rights (SARs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
SAR's, initial term	5 years
Vested, shares	75,000	25,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	75,000	100,000
Deferred Cash Award \| Cowen Group, Inc. 2010 Equity and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred cash awards granted	$ 39.2
Stock compensation award, vesting period	4 years
Convergex Group \| Deferred Cash Award
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred cash awards granted	$ 0.3