Investment Securities (Details 1) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Available for sale securities:
Amortized cost	$ 189,089,000	$ 162,425,000
Unrealized gains	7,065,000	4,237,000
Unrealized losses	(6,397,000)	(5,392,000)
Fair value	189,757,000us-gaap_AvailableForSaleSecurities	161,270,000us-gaap_AvailableForSaleSecurities
Trading securities:
Fair value	55,624,000us-gaap_TradingSecurities	82,013,000us-gaap_TradingSecurities
Purchases of trading securities	300,000
Sales and maturities of trading securities	300,000
Affiliated funds
Available for sale securities:
Amortized cost	189,089,000	162,425,000
Unrealized gains	7,065,000	4,237,000
Unrealized losses	(6,397,000)	(5,392,000)
Fair value	189,757,000	161,270,000
Trading securities:
Fair value	55,521,000	81,913,000
Mortgage-backed securities
Trading securities:
Fair value	27,000	28,000
Common Stock
Trading securities:
Fair value	$ 76,000	$ 72,000

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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The cash outflow to acquire securities classified as trading securities and held for investment purposes. Excludes payments for trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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The cash inflow associated with the sale, maturities, repayments and calls of securities classified as trading securities and held for investment purposes. Excludes proceeds from trading securities purchased and held principally for the purpose of selling them in the near term (thus held for only a short period of time).

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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