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Exchanged shares of our Class B Common Stock ("Class B Stock"), representing all of our then issued and outstanding common stock, with Gabelli Funds, Inc. ("GFI").

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The amount of receivable related to incentive fees during the period.

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Mr. Gabelli has the ability to allocate as portion of management fees to his designee, this element represents the amounts allocated to other recipients.

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Management fee expense is incentive-based and entirely variable compensation in the amount of this percentage of the aggregate pre-tax profits which is paid to Mr. Gabelli or his designee for acting as CEO pursuant to his 2008 Employment Agreement so long as he is an executive of GBL and devotes the substantial majority of his working time to the business.

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The amount of management fee due to the CEO pursuant to his 2008 Employment Agreement now waived by the CEO.

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The amount of receivable related to management fees receivable on closed-end preferred shares during the period.

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Number of shares of common stock issued for each share of common stock the parent company in a spin-off.

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Amortization and depreciation have been estimated on an annual basis for this many years into the future.

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The Company derived a percentage of its total revenues from advisory and management fees, including incentive fees.

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The amount of receivable related to incentive fees relating to The GDL Fund during the period.

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The number of subsidiaries included with the primary entity engaged in the transaction.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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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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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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.

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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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Percentage of vesting of share-based compensation awards.

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Significant Accounting Policies (Details)			12 Months Ended
Significant Accounting Policies (Details)	Nov. 30, 2015 shares	Feb. 09, 1999 Subsidiary shares	Dec. 31, 2015 USD ($) Segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Portion of revenue derived from advisory and management fees			87.00%	85.00%	86.00%
Institutional and private wealth management incentive fees receivable			$ 0	$ 200,000
GDL fund performance fee receivable			3,700,000	800,000
Management fees receivable on closed-end preferred shares			$ 0	6,300,000
Management Fee [Abstract]
Management fee expense percentage			10.00%
Management fee allocated to other employees			$ 1,900,000	4,000,000	$ 2,300,000
Management fee waived					1,400,000
Business Segment [Abstract]
Number of operating segments \| Segment			1
AC [Member] \| Class A [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares of common stock received for each share of Gamco common stock in spin-off (in shares) \| shares	1
AC [Member] \| Class B [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Number of shares of common stock received for each share of Gamco common stock in spin-off (in shares) \| shares	1
Fixed Assets Other Than Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Fixed assets with net book value			$ 394,000	602,000
Accumulated Depreciation			$ 2,500,000	2,400,000
Fixed Assets Other Than Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of assets			4 years
Fixed Assets Other Than Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of assets			7 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Fixed assets with net book value			$ 1,700,000	1,600,000
Depreciation and amortization			618,000	$ 683,000	$ 766,000
Estimated annual depreciation and amortization expense			$ 625,000
Period of estimate for future depreciation and amortization			3 years
Open End Class AAA Shares of the Funds [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Fee percentages paid to distributors based on fund performance			0.25%
Westwood Funds [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Fee percentages paid to distributors based on fund performance			0.50%
Class A Shares of Gabelli Enterprise Mergers and Acquisitions Fund [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Fee percentages paid to distributors based on fund performance			0.45%
Class B and Class C Shares [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Fee percentages paid to distributors based on fund performance			1.00%
Gabelli Funds, Inc [Member] \| Class B [Member]
Business Acquisition, Equity Interests Issued or Issuable [Line Items]
Exchange of common stock (in shares) \| shares		24,000,000
Subsidiaries involved in transaction \| Subsidiary		2
Restricted Stock Awards [Member] \| Vesting in Three Years from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			30.00%
Award vesting period			3 years
Restricted Stock Awards [Member] \| Vesting in Five Years from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			70.00%
Award vesting period			5 years
Restricted Stock Awards [Member] \| Vesting in Year Four from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Five from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Six from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Seven from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Eight from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Nine from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Restricted Stock Awards [Member] \| Vesting in Year Ten from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			10.00%
Stock Options [Member] \| Vesting in Three Years from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			75.00%
Award vesting period			3 years
Stock Options [Member] \| Vesting in Four Years from Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting percentage			25.00%
Award vesting period			4 years