Segment Analysis (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 item	Mar. 31, 2012
Segment Analysis
Number of business segments	3
Information concerning operations
Investment gains/(losses), net	$ 172	$ 132
Investment banking	15,173	6,678
Interest income	8,966	16,761
Interest expense	(1,607)	(2,769)
Net revenues	26,850	48,966
(Loss)/income from continuing operations before income taxes	(13,578)	(2,358)
Reportable segments
Information concerning operations
Net revenues	26,135	46,580
(Loss)/income from continuing operations before income taxes	(5,326)	5,378
Investment banking
Information concerning operations
Investment banking	15,012	4,533
Other revenue	20
Net revenues	15,032	4,533
(Loss)/income from continuing operations before income taxes	3,345	579
MBS & Rates
Information concerning operations
Sales and trading	(7,629)	8,004
Investment banking	161	237
Interest income	8,611	16,427
Interest expense	(1,812)	(4,337)
Other revenue	(53)
Net revenues	(722)	20,331
(Loss)/income from continuing operations before income taxes	(8,254)	5,487
Credit Products
Information concerning operations
Sales and trading	10,821	19,638
Investment banking		1,908
Interest income	257	132
Interest expense	(71)	(99)
Other revenue	818	137
Net revenues	11,825	21,716
(Loss)/income from continuing operations before income taxes	(417)	(688)
Other
Information concerning operations
Investment gains/(losses), net	172	132
Sales and trading	(10)	8
Interest income	98	202
Interest expense	(244)	(59)
Interest expense - Intersegment allocations	520	1,726
Other revenue	179	377
Net revenues	715	2,386
(Loss)/income from continuing operations before income taxes	$ (8,252)	$ (7,736)