Condensed Consolidating Financial Statements (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
REVENUE
Fee and other revenue	$ 326,706	$ 304,074	$ 641,624	$ 594,083
Investment revenue	3,436	5,879	6,613	9,894
Total revenue	330,142	309,953	648,237	603,977
EXPENSES
Fee and other commissions expense	146,673	135,561	288,588	264,621
Investment commissions expense	103	111	180	251
Total commissions expense	146,776	135,672	288,768	264,872
Compensation and benefits	59,030	57,913	118,094	117,208
Transaction and operations support	98,008	58,594	156,222	109,003
Occupancy, equipment and supplies	12,142	11,637	24,353	23,390
Depreciation and amortization	11,053	11,879	21,736	23,545
Total operating expenses	327,009	275,695	609,173	538,018
OPERATING INCOME	3,133	34,258	39,064	65,959
Other (income) expense
Net securities gains		(32,816)		(32,816)
Interest expense	17,637	22,873	35,520	43,486
Other	347	14,856	347	14,856
Total other expenses, net	17,984	4,913	35,867	25,526
(Loss) income before income taxes	(14,851)	29,345	3,197	40,433
Income tax (benefit) expense	10,205	2,941	17,984	(16)
(Loss) income after income taxes	(25,056)	26,404	(14,787)	40,449
NET (LOSS) INCOME	(25,056)	26,404	(14,787)	40,449
Parent [Member]
EXPENSES
Compensation and benefits				(31)
Transaction and operations support	8,845	1,471	10,611	2,495
Total operating expenses	8,845	1,471	10,611	2,464
OPERATING INCOME	(8,845)	(1,471)	(10,611)	(2,464)
Other (income) expense
Other	347	5,520	347	5,520
Total other expenses, net	347	5,520	347	5,520
(Loss) income before income taxes	(9,192)	(6,991)	(10,958)	(7,984)
Income tax (benefit) expense	(3,563)	(2,417)	(4,181)	(2,764)
(Loss) income after income taxes	(5,629)	(4,574)	(6,777)	(5,220)
Equity income (loss) in subsidiaries	(19,427)	30,978	(8,010)	45,669
NET (LOSS) INCOME	(25,056)	26,404	(14,787)	40,449
Subsidiary Guarantors [Member]
REVENUE
Fee and other revenue	352,844	297,495	693,211	582,173
Investment revenue	3,238	5,751	6,181	9,686
Total revenue	356,082	303,246	699,392	591,859
EXPENSES
Fee and other commissions expense	184,742	140,855	364,196	275,943
Investment commissions expense	103	111	180	251
Total commissions expense	184,845	140,966	364,376	276,194
Compensation and benefits	42,292	42,949	86,318	87,091
Transaction and operations support	93,676	64,174	157,698	130,250
Occupancy, equipment and supplies	8,572	8,749	17,591	17,560
Depreciation and amortization	7,967	8,957	15,566	17,994
Total operating expenses	337,352	265,795	641,549	529,089
OPERATING INCOME	18,730	37,451	57,843	62,770
Other (income) expense
Net securities gains		(32,816)		(32,816)
Interest expense	17,637	22,873	35,520	43,486
Other		9,336		9,336
Total other expenses, net	17,637	(607)	35,520	20,006
(Loss) income before income taxes	1,093	38,058	22,323	42,764
Income tax (benefit) expense	15,239	5,058	23,600	2,148
(Loss) income after income taxes	(14,146)	33,000	(1,277)	40,616
Equity income (loss) in subsidiaries	(5,281)	(2,022)	(6,733)	5,053
NET (LOSS) INCOME	(19,427)	30,978	(8,010)	45,669
Non-Guarantors [Member]
REVENUE
Fee and other revenue	71,870	67,045	141,182	130,318
Investment revenue	198	128	432	208
Total revenue	72,068	67,173	141,614	130,256
EXPENSES
Fee and other commissions expense	42,263	37,004	80,136	63,946
Total commissions expense	42,263	37,004	80,136	63,946
Compensation and benefits	16,738	14,964	31,776	30,148
Transaction and operations support	13,163	11,117	24,938	19,398
Occupancy, equipment and supplies	3,570	2,888	6,762	5,830
Depreciation and amortization	3,086	2,922	6,170	5,551
Total operating expenses	78,820	68,895	149,782	124,873
OPERATING INCOME	(6,752)	(1,722)	(8,168)	5,653
Other (income) expense
(Loss) income before income taxes	(6,752)	(1,722)	(8,168)	5,653
Income tax (benefit) expense	(1,471)	300	(1,435)	600
(Loss) income after income taxes	(5,281)	(2,022)	(6,733)	5,053
NET (LOSS) INCOME	(5,281)	(2,022)	(6,733)	5,053
Eliminations [Member]
REVENUE
Fee and other revenue	(98,008)	(60,466)	(192,769)	(118,408)
Total revenue	(98,008)	(60,466)	(192,769)	(118,408)
EXPENSES
Fee and other commissions expense	(80,332)	(42,298)	(155,744)	(75,268)
Total commissions expense	(80,332)	(42,298)	(155,744)	(75,268)
Transaction and operations support	(17,676)	(18,168)	(37,025)	(43,140)
Total operating expenses	(98,008)	(60,466)	(192,769)	(118,408)
Other (income) expense
Equity income (loss) in subsidiaries	24,708	(28,956)	14,743	(50,722)
NET (LOSS) INCOME	$ 24,708	$ (28,956)	$ 14,743	$ (50,722)