Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Commissions and fees	$ 399,691	$ 376,463	$ 405,679
Recurring	75,911	81,916	107,184
Other	8,092	10,673	121,940
Total revenues	483,694	469,052	634,803
Expenses:
Compensation and employee benefits	184,716	188,886	209,323
Transaction processing	100,747	90,271	91,492
Occupancy and equipment	68,563	56,189	57,495
Telecommunications and data processing services	48,477	56,643	51,523
Restructuring charges		9,620
Other general and administrative	72,641	108,466	101,915
Interest expense	2,025	2,217	1,829
Total expenses	477,169	512,292	513,577
Income (loss) before income tax expense (benefit)	6,525	(43,240)	121,226
Income tax expense (benefit)	45,965	(17,322)	29,656
Net (loss) income	$ (39,440)	$ (25,918)	$ 91,570
(Loss) income per share:
Basic (in dollars per share)	$ (1.19)	$ (0.79)	$ 2.70
Diluted (in dollars per share)	$ (1.19)	$ (0.79)	$ 2.63
Basic weighted average number of common shares outstanding (in shares)	33,009	32,906	33,907
Diluted weighted average number of common shares outstanding (in shares)	33,009	32,906	34,815