Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Operating Activities:
Net income/(loss)	$ 60,350	$ 19,510
Adjustments to reconcile net income/(loss) to net cash provided by/(used in) operating activities:
Depreciation and amortization of fixed assets	3,992	4,300
Deferred income taxes	(2,487)	5,933
Loss on sale of FAMCO	0	(1,876)
Share-based and deferred compensation	21,067	11,012
Amortization of intangible assets	6,954	6,221
Amortization of forgivable loans	3,961	4,827
Decrease/(increase) in operating assets:
Cash and cash equivalents segregated for regulatory purposes	4,983	5,999
Receivables:
Customers	(14,036)	(17,580)
Brokers, dealers and clearing organizations	(164,077)	(94,186)
Securities purchased under agreements to resell	(95,805)	(81,990)
Net financial instruments and other inventory positions owned	136,592	(163,710)
Investments	(13,124)	(19,375)
Other assets	3,298	2,945
Payables:
Customers	2,835	(1,229)
Brokers, dealers and clearing organizations	56,622	65,071
Accrued compensation	25,741	(26,425)
Other liabilities and accrued expenses	(4,559)	(23,566)
Increase (Decrease) in Liabilities Held-for-sale	0	(465)
Increase (Decrease) in Assets Held-for-sale	0	605
Net cash provided by/(used in) operating activities	32,307	(300,227)
Investing Activities:
Payments to Acquire Businesses, Net of Cash Acquired	0	(24,726)
Sale of FAMCO	0	250
Purchases of fixed assets, net	(5,270)	(3,257)
Net cash used in investing activities	(5,270)	(27,733)
Financing Activities:
Increase/(decrease) in short-term financing	(175,916)	186,275
Proceeds from Issuance of Senior Long-term Debt	50,000	0
Repayments of Long-term Debt	(50,000)	0
Increase in securities sold under agreements to repurchase	62,576	28,914
Increase/(decrease) in noncontrolling interests	(16,402)	91,192
Repurchase of common stock	(10,563)	(69,947)
Excess tax benefit from share-based compensation	1,006	39
Proceeds from stock option transactions	3,644	0
Net cash provided by/(used in) financing activities	(135,655)	236,473
Currency adjustment:
Effect of exchange rate changes on cash	(118)	77
Net decrease in cash and cash equivalents	(108,736)	(91,410)
Cash and cash equivalents at beginning of year	123,683	105,371
Cash and cash equivalents at end of year	14,947	13,961
Supplemental disclosure of cash flow information –
Interest	17,116	17,938
Income taxes	45,284	2,870
Non-cash financing activities –
Issuance of common stock for retirement plan obligations: 103,598 shares and 96,049 shares for the nine months ended September 30, 2014 and 2013, respectively	4,156	3,939
Issuance of restricted common stock for annual equity award: 402,074 shares and 431,582 shares for the nine months ended September 30, 2014 and 2013, respectively	$ 16,131	$ 17,699