Investment Securities (Details) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)
Available for sale securities:
Amortized cost		$ 47,300	$ 162,425
Unrealized gains		759	4,237
Unrealized losses		(6,682)	(5,392)
Fair value		41,377	161,270
Trading securities:
Fair value		29,813	82,013
Equity method securities		220,553
Total investment securities		291,743	243,283
Transfers to equity method securities		160,200
Unrealized losses	$ 2,100
Mortgage-backed securities
Trading securities:
Fair value		20	28
Corporate bonds
Trading securities:
Fair value		5
Common Stock
Trading securities:
Fair value		87	72
Sponsored funds
Available for sale securities:
Amortized cost		46,800	160,675
Unrealized gains		434	2,177
Unrealized losses		(6,682)	(5,392)
Fair value		40,552	157,460
Trading securities:
Fair value		29,701	81,913
Equity method securities		$ 217,380
Number of investment securities held \| item		0
Sponsored privately offered funds measured at net asset value
Available for sale securities:
Amortized cost		$ 500	1,750
Unrealized gains		325	2,060
Fair value		825	$ 3,810
Trading securities:
Equity method securities		$ 3,173

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

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