Condensed Consolidated Statements of Financial Condition (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Assets
Cash and cash equivalents	$ 228,828	$ 284,188
Cash restricted or segregated under regulations and other	65,718	71,496
Deposits with clearing organizations	25,583	25,538
Securities owned, at fair value	5,763	5,277
Receivables from brokers, dealers and clearing organizations	944,125	871,315
Receivables from customers	589,334	472,509
Premises and equipment, net	42,590	43,023
Capitalized software, net	47,691	51,258
Goodwill		274,292
Other intangibles, net	37,844	39,594
Income taxes receivable	6,919	6,838
Deferred taxes	34,534	16,493
Other assets	20,452	16,248
Total assets	2,049,381	2,178,069
Liabilities:
Accounts payable and accrued expenses	148,069	181,224
Short-term bank loans	8,415	1,606
Payables to brokers, dealers and clearing organizations	1,004,906	1,079,773
Payables to customers	440,396	207,738
Securities sold, not yet purchased, at fair value	1,757	438
Income taxes payable	8,659	11,460
Deferred taxes	382	719
Term debt	22,375	23,997
Total liabilities	1,634,959	1,506,955
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; 51,961,710 and 51,899,229 shares issued at June 30, 2012 and December 31, 2011, respectively	520	519
Additional paid-in capital	239,575	249,469
Retained earnings	411,706	653,344
Common stock held in treasury, at cost; 13,595,310 and 12,679,948 shares at June 30, 2012 and December 31, 2011, respectively	(245,572)	(240,559)
Accumulated other comprehensive income (net of tax)	8,193	8,341
Total stockholders' equity	414,422	671,114
Total liabilities and stockholders' equity	$ 2,049,381	$ 2,178,069