Condensed Consolidated Statements of Financial Condition (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Assets
Cash and cash equivalents	$ 228,461	$ 261,897
Cash restricted or segregated under regulations and other	71,038	71,202
Deposits with clearing organizations	33,635	74,771
Securities owned, at fair value	21,943	7,436
Receivables from brokers, dealers and clearing organizations	2,094,468	1,018,342
Receivables from customers	1,376,047	591,004
Premises and equipment, net	59,484	66,171
Capitalized software, net	38,072	37,892
Goodwill, net	14,332
intangibles, net	32,700	31,201
Income taxes receivable	539	54
Deferred taxes	30,864	34,130
Other assets	23,411	15,787
Total assets	4,024,994	2,209,887
Liabilities:
Accounts payable and accrued expenses	186,145	175,931
Short-term bank loans	89,926	73,539
Payables to brokers, dealers and clearing organizations	1,660,229	1,025,268
Payables to customers	1,611,985	469,264
Securities sold, not yet purchased, at fair value	22,856	2,953
Income taxes payable	14,156	14,805
Deferred taxes	1,141	363
Term debt	20,937	30,332
Total liabilities	3,607,375	1,792,455
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; 52,229,962 and 52,158,374 shares issued at September 30, 2014 and December 31, 2013, respectively	522	522
Additional paid-in capital	237,561	240,057
Retained earnings	474,481	436,570
Common stock held in treasury, at cost; 17,444,851 and 16,005,500 shares at September 30, 2014 and December 31, 2013, respectively	(295,995)	(268,253)
Accumulated other comprehensive income (net of tax)	1,050	8,536
Total stockholders' equity	417,619	417,432
Total liabilities and stockholders' equity	$ 4,024,994	$ 2,209,887