CONDENSED CONSOLIDATED STATEMENTS OF INCOME UNAUDITED (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues
Investment advisory and incentive fees	$ 67,783	$ 62,911
Institutional research services	2,343	3,649
Distribution fees and other income	11,623	10,345
Total revenues	81,749	76,905
Expenses
Compensation	34,554	33,417
Management fee	4,184	3,113
Distribution costs	10,177	13,429
Other operating expenses	5,822	6,186
Total expenses	54,737	56,145
Operating income	27,012	20,760
Other income (expense)
Net gain from investments	13,878	8,740
Interest and dividend income	1,236	1,936
Interest expense	(4,404)	(2,867)
Total other income (expense), net	10,710	7,809
Income before income taxes	37,722	28,569
Income tax provision	13,756	10,288
Net income	23,966	18,281
Net income attributable to noncontrolling interests	130	638
Net income attributable to GAMCO Investors, Inc.'s shareholders	$ 23,836	$ 17,643
Net income attributable to GAMCO Investors, Inc.'s shareholders per share:
Basic (in dollars per share)	$ 0.90	$ 0.66
Diluted (in dollars per share)	$ 0.90	$ 0.65
Weighted average shares outstanding:
Basic (in shares)	26,415	26,901
Diluted (in shares)	26,533	27,008
Dividends declared: (in dollars per share)	$ 0.04	$ 0.03