Consolidated Statements Of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenues:
Commissions		$ 172,264	$ 182,104	$ 347,538	$ 380,034
Principal transactions		95,703	126,426	212,560	247,374
Investment banking		185,261	133,125	312,113	233,783
Asset management and service fees		172,914	144,567	335,653	289,099
Interest		108,951	65,780	209,904	128,607
Other income		7,198	17,405	15,950	24,595
Total revenues		742,291	669,407	1,433,718	1,303,492
Interest expense		16,644	17,262	32,540	31,373
Net revenues	[1]	725,647	652,145	1,401,178	1,272,119
Non-interest expenses:
Compensation and benefits		453,876	460,023	890,263	871,136
Occupancy and equipment rental		57,892	58,746	110,437	116,002
Communications and office supplies		34,192	37,426	68,036	74,086
Commissions and floor brokerage		11,232	12,145	21,955	23,876
Other operating expenses		85,257	68,012	148,270	127,313
Total non-interest expenses		642,449	636,352	1,238,961	1,212,413
Income from operations before income tax expense		83,198	15,793	162,217	59,706
Provision for income taxes		30,387	6,022	43,894	22,880
Net income		52,811	9,771	118,323	36,826
Preferred dividends		2,344		4,688
Net income available to common shareholders		$ 50,467	$ 9,771	$ 113,635	$ 36,826
Earnings per common share:
Basic		$ 0.74	$ 0.15	$ 1.66	$ 0.55
Diluted		$ 0.63	$ 0.13	$ 1.41	$ 0.48
Weighted-average number of common shares outstanding:
Basic		68,556	66,792	68,471	67,186
Diluted		80,021	75,982	80,391	76,084

[1] No individual client accounted for more than 10 percent of total net revenues for the three and six months ended June 30, 2017 or 2016.