Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Revenues
Investment banking	$ 81,923	$ 57,383	$ 264,737	$ 158,082
Brokerage	92,035	84,220	301,053	198,599
Management fees	7,546	8,223	22,336	25,587
Incentive income	33	1,945	97	6,217
Interest and dividends	26,448	14,318	77,511	27,324
Reimbursement from affiliates	353	484	1,066	2,631
Aircraft lease revenue	375	934	1,509	3,036
Reinsurance premiums	8,378	7,186	26,251	21,957
Other revenues	1,634	3,402	3,846	6,147
Consolidated Funds
Interest and dividends	2,294	871	8,565	4,253
Other revenues	9	(136)	14	498
Total revenues	221,028	178,830	706,985	454,331
Interest and dividends expense	26,000	15,132	74,846	37,273
Revenue, Net	195,028	163,698	632,139	417,058
Expenses
Employee compensation and benefits	127,303	103,282	394,288	282,066
Floor brokerage and trade execution	23,217	25,817	82,317	48,218
Underwriting expenses	4,412	0	13,260	0
Professional, advisory and other fees	7,698	7,001	20,541	23,344
Service fees	4,880	3,983	14,927	9,927
Communications	7,894	6,423	22,566	17,186
Occupancy and equipment	10,140	9,656	30,385	25,252
Depreciation and amortization	3,139	3,452	9,558	9,612
Client services and business development	6,671	5,551	22,767	20,505
Reinsurance claims, commissions and amortization of deferred acquisition costs	8,773	7,157	27,428	20,610
Restructuring costs	0	222	0	8,763
Other expenses	5,335	4,960	15,007	12,550
Consolidated Funds
Interest and dividends	1,270	1,234	5,660	7,325
Professional, advisory and other fees	191	205	748	901
Floor brokerage and trade execution	39	64	192	278
Other expenses	187	209	667	919
Total expenses	211,149	179,216	660,311	487,456
Other income (loss)
Net gains (losses) on securities, derivatives and other investments	32,040	18,326	64,728	63,101
Bargain purchase gain, net of tax	0	0	0	7,946
Gain (loss) on debt extinguishment	0	0	(556)	0
Consolidated Funds
Net realized and unrealized gains (losses) on investments and other transactions	8,280	9,073	52,284	48,154
Net realized and unrealized gains (losses) on derivatives	1,664	220	6,258	5,405
Net gains (losses) on foreign currency transactions	(2)	8	250	(299)
Total other income (loss)	41,982	27,627	122,964	124,307
Income (loss) before income taxes	25,861	12,109	94,792	53,909
Income tax expense (benefit)	5,083	2,281	15,999	3,407
Net income (loss)	20,778	9,828	78,793	50,502
Net income (loss) attributable to redeemable non-controlling interests in consolidated subsidiaries and funds	(5,290)	(5,162)	(41,053)	(35,412)
Net income (loss) attributable to Cowen Inc.	15,488	4,666	37,740	15,090
Preferred stock dividends	1,698	1,698	5,094	5,094
Net income (loss) attributable to Cowen Inc. common stockholders	$ 13,790	$ 2,968	$ 32,646	$ 9,996
Weighted average common shares outstanding:
Basic (in shares)	29,610	31,271	29,662	29,004
Diluted (in shares)	30,844	32,246	30,613	30,011
Earnings (loss) per share:
Earnings Per Share, Basic (in dollars per share)	$ 0.47	$ 0.09	$ 1.10	$ 0.34
Earnings Per Share, Diluted (in dollars per share)	$ 0.45	$ 0.09	$ 1.07	$ 0.33