CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME UNAUDITED (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Comprehensive Income [Abstract]
Net income	$ 27,912	$ 14,863	$ 50,592	$ 38,829
Other comprehensive income, net of tax
Foreign currency translation	1	22	(48)	5
Net unrealized gains on securities available for sale, net of tax	(6,900)	(2,579)	(860)	878
Other comprehensive income	(6,899)	(2,557)	(908)	883
Comprehensive income	21,013	12,306	49,684	39,712
Less: Comprehensive income attributable to noncontrolling interests	(19)	242	(154)	112
Comprehensive income attributable to GAMCO Investors, Inc.	$ 20,994	$ 12,548	$ 49,530	$ 39,824

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

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- Definition

Net of tax and reclassification adjustments of the change in the balance sheet adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity. Also includes the following: gain (loss) on foreign currency forward exchange contracts; foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements; and gain (loss) on a derivative instrument or nonderivative financial instrument that may give rise to a foreign currency transaction gain (loss) that has been designated and qualified as a hedging instrument for hedging of the foreign currency exposure of a net investment in a foreign operation.

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- Definition

Net of tax amount of unrealized holding gain (loss) before reclassification adjustments and transfers on available-for-sale securities.

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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