Condensed Consolidated Statements of Financial Condition (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Assets
Cash and cash equivalents	$ 205,762	$ 275,210
Cash restricted or segregated under regulations and other	37,876	38,080
Deposits with clearing organizations	89,674	72,527
Securities owned, at fair value	12,204	12,073
Receivables from brokers, dealers and clearing organizations	881,887	644,614
Receivables from customers	110,225	107,935
Premises and equipment, net	56,967	60,306
Capitalized software, net	38,650	38,333
Goodwill	12,041	12,803
Intangibles, net	30,789	31,595
Income taxes receivable	2,114	105
Deferred taxes	28,270	37,209
Other assets	22,992	20,059
Total assets	1,529,451	1,350,849
Liabilities:
Accounts payable and accrued expenses	163,795	199,211
Short-term bank loans	107,269	78,360
Payables to brokers, dealers and clearing organizations	788,964	600,041
Payables to customers	29,775	11,132
Securities sold, not yet purchased, at fair value	8,552	8,253
Income taxes payable	10,795	19,772
Deferred taxes		703
Term debt	14,612	17,781
Total liabilities	1,123,762	935,253
Commitments and contingencies
Stockholders' Equity:
Preferred stock, $0.01 par value; 1,000,000 shares authorized; no shares issued or outstanding
Common stock, $0.01 par value; 100,000,000 shares authorized; 52,265,654 and 52,229,962 shares issued at March 31, 2015 and December 31, 2014, respectively	522	522
Additional paid-in capital	231,273	240,135
Retained earnings	504,195	487,462
Common stock held in treasury, at cost; 18,038,374 and 18,000,756 shares at March 31, 2015 and December 31, 2014, respectively	(313,560)	(306,629)
Accumulated other comprehensive income (net of tax)	(16,741)	(5,894)
Total stockholders' equity	405,689	415,596
Total liabilities and stockholders' equity	$ 1,529,451	$ 1,350,849