Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Revenues
Investment management fees	$ 260,557	$ 187,875	$ 135,063
Distribution and service fees	78,965	56,866	43,792
Administration and transfer agent fees	48,185	33,779	23,878
Other income and fees	1,508	1,566	1,919
Total revenues	389,215	280,086	204,652
Operating Expenses
Employment expenses	131,768	105,571	92,543
Distribution and administration expenses	97,786	72,210	60,176
Other operating expenses	38,321	34,017	30,157
Other operating expenses of consolidated sponsored investment products	798	315
Restructuring and severance	203	1,597	2,008
Depreciation expense	2,422	1,810	1,847
Amortization expense	4,413	4,121	4,018
Total operating expenses	275,711	219,641	190,749
Operating Income	113,504	60,445	13,903
Other Income (Expense)
Realized and unrealized gain (loss) on investments, net	2,350	1,891	(256)
Realized and unrealized gain on investments of consolidated sponsored investment products, net	3,515	2,072
Other income (expense), net	74	(38)	(194)
Total other income (expense), net	5,939	3,925	(450)
Interest Income (Expense)
Interest expense	(782)	(854)	(782)
Interest and dividend income	664	710	321
Interest and dividend income of investments of consolidated sponsored investment products	2,583	577
Total interest income (expense), net	2,465	433	(461)
Income Before Income Taxes	121,908	64,803	12,992
Income tax expense (benefit)	44,778	27,030	(132,428)
Net Income	77,130	37,773	145,420
Noncontrolling interests	(1,940)	(101)
Preferred stockholder dividends			(9,482)
Allocation of earnings to preferred stockholders		(64)	(24,260)
Net Income Attributable to Common Stockholders	$ 75,190	$ 37,608	$ 111,678
Earnings per share-Basic	$ 9.18	$ 4.87	$ 17.98
Earnings per share-Diluted	$ 8.92	$ 4.66	$ 16.34
Weighted Average Shares Outstanding-Basic (in thousands)	8,188	7,727	6,211
Weighted Average Shares Outstanding-Diluted (in thousands)	8,433	8,073	6,834