Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ (7,995)	$ 19,418
Adjustments to reconcile net income (loss) to net cash provided by / (used in) operating activities:
Depreciation and amortization	3,067	2,138
Amortization of Debt Issue Costs	291	291
Amortization of debt discount	1,665	1,524
Tax benefits from share based payment arrangements	(515)	1,536
Share-based compensation	6,423	4,162
Deferred tax benefit	(2,384)	3,663
Deferred rent obligations	107	351
Net loss on disposal of fixed assets	0	31
Contingent liability adjustment	(2,135)	0
Purchases of securities owned, at fair value	(1,293,147)	(1,026,453)
Proceeds from sales of securities owned, at fair value	1,263,611	1,252,567
Proceeds from sales of securities sold, not yet purchased, at fair value	1,068,580	525,223
Payments to cover securities sold, not yet purchased, at fair value	(910,751)	(592,564)
Net (gains) losses on securities, derivatives and other investments	(2,836)	(38,661)
Consolidated Funds
Purchases of securities owned, at fair value	(7,355)	0
Proceeds from sales of securities owned, at fair value	878	0
Proceeds From Securities Sold Not Yet Purchased At Fair Value	2,049	0
Payments to Cover Securities Sold Not Yet Purchased at Fair Value	855	0
Purchases of other investments	(212,028)	(985)
Proceeds from sales of other investments	855	4,845
Net realized and unrealized (gains) losses on investments and other transactions	245	(4,769)
(Increase) decrease in operating assets:
Cash collateral pledged	(72)	(617)
Securities owned, at fair value, held at broker dealer	8,004	13,164
Receivable on derivative contracts, at fair value	(6,106)	(7,076)
Securities borrowed	0	676,100
Receivable from brokers	(4,785)	(24,843)
Fees receivable, net of allowance	(6,759)	(19,588)
Due from related parties	5,264	2,377
Other assets	(11,257)	(3,565)
Consolidated Funds
Cash and cash equivalents	1,586	(142)
Receivable on derivative contracts	(125)	0
Other assets	(738)	750
Increase (decrease) in operating liabilities:
Securities sold, not yet purchased, at fair value, held at broker dealer	(6,141)	16,039
Payable for derivative contracts, at fair value	3,951	2,896
Securities loaned	0	(682,493)
Payable to brokers	(107,952)	(107,903)
Compensation payable	(128,152)	(70,004)
Fees payable	(3,892)	15,352
Due to related parties	(95)	(76)
Accounts payable, accrued expenses and other liabilities	3,841	(3,438)
Consolidated Funds
Contributions received in advance	1,750	0
Payable to brokers	2,314	0
Payable for derivative contracts, at fair value	2	0
Due to related parties	265	0
Accounts payable, accrued expenses and other liabilities	707	67
Net cash provided by / (used in) operating activities	(340,620)	(40,683)
Cash flows from investing activities:
Purchases of other investments	(16,187)	(5,760)
Payments to acquire loan held for investment	0	(15,000)
Proceeds from sales of other investments	5,937	35,050
Proceeds from loans held for investments	39,200	0
Purchase of fixed assets	(12,383)	(301)
Net cash provided by / (used in) investing activities	16,567	13,989
Cash flows from financing activities:
Borrowings on notes and other debt	22,072	2,140
Repayments on notes and other debt	(660)	(1,030)
Income tax effect from share-based payment arrangements	(515)	1,536
Purchase of treasury stock	(3,571)	(7,205)
Cash paid to acquire net assets (contingent liability payable)	0	(108)
Capital withdrawals to redeemable non-controlling interests in operating entities	(2,267)	(4,457)
Consolidated Funds
Capital contributions by redeemable non-controlling interests in Consolidated Funds	217,633	3,379
Capital withdrawals to redeemable non-controlling interests in Consolidated Funds	(78)	(2,404)
Net cash provided by / (used in) financing activities	232,614	(8,149)
Change in cash and cash equivalents	(91,439)	(34,843)
Cash and cash equivalents at beginning of period	158,485	129,509
Cash and cash equivalents at end of period	67,046	94,666
Supplemental information
Purchase of treasury stock, at cost, through net settlement	4,012	2,777
Preferred stock dividends declared	1,698	0
Net Assets of Deconsolidated Entity	$ 73,309	$ 0