Number of consolidated funds

No definition available.

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- Definition

For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, within one year (or one operating cycle, if longer) of the balance sheet date. Such receivable is reduced by allowances attributable to, for instance, credit risk associated with a lessee.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39927-112707

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property by the lessor or lessee, respectively.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7501430&loc=d3e39896-112707

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents a sum total of expenses not separately reflected on the income statement for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04.7)
-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.4,6)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

Name:	us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of premium revenue earned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 235
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-16)
-URI http://asc.fasb.org/extlink&oid=34713774&loc=d3e574960-122915

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The net carrying amount of the consolidated Variable Interest Entity's assets and liabilities included in the reporting entity's statement of financial position.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_LeaseholdImprovementsMember
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- Details

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- Details

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Significant Accounting Policies All Other - Quarterly (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) cowenfund	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) cowenfund	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) cowenfund
Total net assets of consolidated VIEs	$ 452,000		$ 452,000		$ 1,500
Deferred rent	10,400		10,400		12,000
Deferred Rent Asset, Net, Current	100		100		$ 300
Other Expenses	$ 11,898	$ 3,783	$ 32,328	$ 11,442
Variable Interest Entity, Primary Beneficiary [Member]
Number of funds, Consolidated \| cowenfund	3		3		3
Other investment companies
Number of funds, Consolidated \| cowenfund	6		6
Investment Company
Number of funds, Consolidated \| cowenfund	2		2
Assets Held under Capital Leases [Member]
Property, Plant and Equipment, Useful Life			5 years
Minimum \| Telephone and computer equipment
Property, Plant and Equipment, Useful Life			3 years
Minimum \| Computer Software, Intangible Asset [Member]
Property, Plant and Equipment, Useful Life			3 years
Minimum \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life			5 years
Minimum \| Leasehold improvements
Property, Plant and Equipment, Useful Life			5 years
Minimum \| Aircraft [Member]
Property, Plant and Equipment, Useful Life			10 years
Minimum \| Flight Equipment [Member]
Property, Plant and Equipment, Useful Life			4 years
Maximum \| Telephone and computer equipment
Property, Plant and Equipment, Useful Life			8 years
Maximum \| Computer Software, Intangible Asset [Member]
Property, Plant and Equipment, Useful Life			7 years
Maximum \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life			8 years
Maximum \| Leasehold improvements
Property, Plant and Equipment, Useful Life			15 years
Maximum \| Aircraft [Member]
Property, Plant and Equipment, Useful Life			20 years
Maximum \| Flight Equipment [Member]
Property, Plant and Equipment, Useful Life			10 years
Luxembourg Reinsurance Companies [Member]
Supplementary Insurance Information, Premium Revenue	$ 8,900		$ 23,200
Other Expenses	$ 8,600		$ 20,900