Deferred Compensation Arrangement with Individual, Interest Rate

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- Definition

Deferred Compensation Arrangement with Individual, Total Compensation Cost Not yet Recognized

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No definition available.

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- Definition

Deferred cash award granted

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- Definition

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

+ References

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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-Publisher FASB
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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-Publisher FASB
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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.

+ References

No definition available.

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- Definition

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

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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.

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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 ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares	0	88,504
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	0
Equity Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-compensation expense recognized in connection with compensation plan	$ 34.0	$ 37.0	$ 28.4
Tax benefit of stock-compensation expense recognized in connection with compensation plan	$ 8.8	$ 9.7	$ 7.7
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	$ 62.6
Vested, shares	2,291,032	1,961,824
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	5,364,486	5,962,295	5,579,293
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	0
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	216,912	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
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	0	0	75,000
Deferred Cash Award \| Cowen Group, Inc. 2010 Equity and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation award, vesting period	4 years
Deferred cash awards granted	$ 42.5
Deferred cash award, interest rate	0.70%
Deferred cash awards, unrecognized compensation expense	$ 60.3