v2.4.0.6

Investment In Unconsolidated Affiliate (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended					1 Months Ended		3 Months Ended	6 Months Ended	1 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Jun. 30, 2012 LSV [Member]	Dec. 31, 2011 LSV [Member]	Jul. 31, 2012 LSV Employee Group II [Member]	Apr. 30, 2011 LSV Employee Group II [Member]	Jun. 30, 2012 LSV Employee Group II [Member]	Jun. 30, 2012 LSV Employee Group II [Member]	Apr. 30, 2011 Bank Of America [Member] LSV Employee Group II [Member]	Jun. 30, 2012 Maximum [Member] LSV [Member]
Investments in and Advances to Affiliates [Line Items]
Income (Loss) from Equity Method Investments	$ 22,712	$ 29,530	$ 50,042	$ 58,479
Equity method investment, ownership percentage						39.80%	41.20%						50.00%
Total investment in LSV	63,553		63,553		60,954
Investment in LSV in excess of the underlying equity in net assets	3,499		3,499
Partnership distribution payments received from LSV			47,443	50,760
Variable interest entity, principal payment								272			468
Variable interest entity, unpaid principal balance of the term loan								2,457		2,729	2,729
Amount financed through new term loan												3,655
Purchase partnership interest									4,300
Goodwill						$ 3,062
Maturity of term loan, years										four

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