CONDENSED CONSOLIDATED STATEMENTS OF INCOME UNAUDITED (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues
Investment advisory and incentive fees	$ 87,797	$ 72,607
Distribution fees and other income	14,873	11,353
Institutional research services	1,807	2,221
Total revenues	104,477	86,181
Expenses
Compensation	43,897	35,652
Management fee	4,728	3,980
Distribution costs	13,963	11,010
Other operating expenses	5,390	4,812
Total expenses	67,978	55,454
Operating income	36,499	30,727
Other income (expense)
Net gain from investments	6,944	12,291
Interest and dividend income	1,141	1,345
Interest expense	(1,992)	(3,488)
Shareholder-designated contribution	0	(5,000)
Total other income, net	6,093	5,148
Income before income taxes	42,592	35,875
Income tax provision	14,616	13,195
Net income	27,976	22,680
Net income attributable to noncontrolling interests	22	135
Net income attributable to GAMCO Investors, Inc.'s shareholders	$ 27,954	$ 22,545
Net income attributable to GAMCO Investors, Inc.'s shareholders
Basic (in dollars per share)	$ 1.10	$ 0.88
Diluted (in dollars per share)	$ 1.09	$ 0.88
Weighted average shares outstanding:
Basic (in shares)	25,481	25,742
Diluted (in shares)	25,684	25,758
Dividends declared: (in dollars per share)	$ 0.06	$ 0.05