Investment in Securities, Investment in Sponsored Registered Investment Companies (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014	Sep. 30, 2014
Available for sale securities:
Available for sale Securities, Cost	$ 79,139	$ 38,178	$ 38,650
Available for sale Securities, Fair Value	108,495	79,846	77,288
Investment in Securities, Fair Value	126,917	259,537	254,630
Investment in Sponsored Registered Investment Companies [Member]
Available for sale securities:
Investment in Securities, Cost	105,048	23,861	23,742
Investment in Securities, Fair Value	115,046	39,537	39,520
Investment in Sponsored Registered Investment Companies [Member] \| Trading Securities [Member]
Trading securities:
Trading Securities, Cost	40,097	1	1
Trading Securities, Fair Value	41,820	1	1
Investment in Sponsored Registered Investment Companies [Member] \| Trading Securities [Member] \| Mutual Funds [Member]
Trading securities:
Trading Securities, Cost	40,097	1	1
Trading Securities, Fair Value	41,820	1	1
Investment in Sponsored Registered Investment Companies [Member] \| Available-for-sale Securities [Member]
Available for sale securities:
Available for sale Securities, Cost	64,951	23,860	23,741
Available for sale Securities, Fair Value	73,226	39,536	39,519
Investment in Sponsored Registered Investment Companies [Member] \| Available-for-sale Securities [Member] \| Mutual Funds [Member]
Available for sale securities:
Available for sale Securities, Cost	1,883	1,898	1,922
Available for sale Securities, Fair Value	2,877	3,213	3,377
Investment in Sponsored Registered Investment Companies [Member] \| Available-for-sale Securities [Member] \| Closed end Funds [Member]
Available for sale securities:
Available for sale Securities, Cost	63,068	21,962	21,819
Available for sale Securities, Fair Value	$ 70,349	$ 36,323	$ 36,142

This item represents a parenthetical disclosure for the cost of securities.

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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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.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

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

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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

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