Consolidated Statements of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Revenues
Commissions	$ 51,989	$ 47,186
Information and post-trade services	8,079	3,703
Technology products and services	2,036	1,233
Investment income	146	132
Other	1,148	1,397
Total revenues	63,398	53,651
Expenses
Employee compensation and benefits	18,609	15,016
Depreciation and amortization	4,121	2,286
Technology and communications	4,492	3,146
Professional and consulting fees	3,972	4,303
Occupancy	1,089	797
Marketing and advertising	1,209	935
General and administrative	2,198	2,497
Total expenses	35,690	28,980
Income before income taxes from continuing operations	27,708	24,671
Provision for income taxes	10,233	9,126
Net income from continuing operations	17,475	15,545
Loss from discontinued operations, net of income taxes		(219)
Net income	$ 17,475	$ 15,326
Basic earnings per common share
Income from continuing operations	$ 0.47	$ 0.42
Loss from discontinued operations
Net income per common share	$ 0.47	$ 0.42
Diluted earnings per common share
Income from continuing operations	$ 0.46	$ 0.41
Loss from discontinued operations
Net income per common share	$ 0.46	$ 0.41
Cash dividends declared per common share	$ 0.16	$ 0.13
Weighted average shares outstanding
Basic	37,121	36,774
Diluted	38,096	37,673