Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Revenues
Investment management fees	$ 300,663	$ 260,557	$ 187,875
Distribution and service fees	91,950	78,965	56,866
Administration and transfer agent fees	56,016	48,185	33,779
Other income and fees	1,969	1,508	1,566
Total revenues	450,598	389,215	280,086
Operating Expenses
Employment expenses	139,809	131,768	105,571
Distribution and administration expenses	123,665	97,786	72,210
Other operating expenses	46,531	38,321	34,017
Other operating expenses of consolidated sponsored investment products	3,038	798	315
Restructuring and severance	294	203	1,597
Depreciation and other amortization	2,763	2,422	1,810
Amortization expense	3,778	4,413	4,121
Total operating expenses	319,878	275,711	219,641
Operating Income	130,720	113,504	60,445
Other Income (Expense)
Realized and unrealized gain on investments, net	914	2,350	1,891
Realized and unrealized (loss) gain on investments of consolidated sponsored investment products, net	(4,648)	3,515	2,072
Other income (expense), net	891	74	(38)
Total other (expense) income, net	(2,843)	5,939	3,925
Interest Income (Expense)
Interest expense	(537)	(782)	(854)
Interest and dividend income	1,706	664	710
Interest and dividend income of investments of consolidated sponsored investment products	7,268	2,583	577
Total interest income, net	8,437	2,465	433
Income Before Income Taxes	136,314	121,908	64,803
Income tax expense	39,349	44,778	27,030
Net Income	96,965	77,130	37,773
Noncontrolling interests	735	(1,940)	(101)
Allocation of earnings to preferred stockholders	0		(64)
Net Income Attributable to Common Stockholders	$ 97,700	$ 75,190	$ 37,608
Earnings per share-Basic	$ 10.75	$ 9.18	$ 4.87
Earnings per share-Diluted	$ 10.51	$ 8.92	$ 4.66
Cash dividends declared per share	$ 1.35
Weighted Average Shares Outstanding-Basic (in thousands)	9,091	8,188	7,727
Weighted Average Shares Outstanding-Diluted (in thousands)	9,292	8,433	8,073