Consolidated Statements of Cash Flows (USD $)	9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Operating Activities:
Net income/(loss)	$ 57,118,000	$ (39,487,000)
Adjustments to reconcile net income to net cash (used in)/provided by operating activities:
Amortization of loans and advances to financial advisors and other employees	42,262,000	35,486,000
Amortization of premium on available-for-sale securities	9,201,000	5,349,000
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	986,000	(916,000)
Amortization of intangible assets	3,588,000
Deferred income taxes	23,777,000	(60,586,000)
Stock-based compensation	19,562,000	183,602,000
Excess tax benefits from stock-based compensation	(25,188,000)	(14,280,000)
Gain on the sale of investments	(60,000)	(1,234,000)
Other, net	1,156,000	(5,881,000)
Decrease/(increase) in operating assets:
Cash segregated for regulatory purposes and restricted cash	5,985,000
Receivables:
Brokerage clients	(49,174,000)	(120,389,000)
Brokers, dealers and clearing organizations	11,757,000	73,327,000
Securities purchased under agreements to resell	2,613,000	(11,221,000)
Trading securities owned, including those pledged	(82,274,000)	(176,664,000)
Loans originated as mortgages held for sale	(638,596,000)	(761,075,000)
Proceeds from mortgages held for sale	608,853,000	715,151,000
Loans and advances to financial advisors and other employees	(30,265,000)	(29,362,000)
Other assets	(37,058,000)	32,851,000
Increase/(decrease) in operating liabilities:
Brokerage clients	29,207,000	3,656,000
Brokers, dealers and clearing organizations	(63,977,000)	72,098,000
Drafts	(27,871,000)	40,923,000
Trading securities sold, but not yet purchased	72,050,000	(5,983,000)
Other liabilities and accrued expenses	(82,110,000)	(3,061,000)
Net cash (used in)/provided by operating activities	(129,334,000)	(46,251,000)
Investing Activities:
Maturities, calls and principal paydowns on available-for-sale securities	535,499,000	150,931,000
Maturities, calls and principal paydowns on held-to-maturity securities	800,000
Sale or maturity of investments	74,437,000	79,195,000
Sale of bank branch		13,905,000
Sale of bank foreclosed assets held for sale	808,000	2,096,000
Increase in bank loans, net	(178,275,000)	(27,531,000)
Payments for:
Purchase of available-for-sale securities	(868,769,000)	(395,646,000)
Purchase of held-to-maturity securities	(80,115,000)	(42,931,000)
Purchase of investments	(71,991,000)	(98,794,000)
Purchase of fixed assets	(32,561,000)	(21,886,000)
Purchase of bank foreclosed assets held for sale	(225,000)
Acquisitions		(500,000)
Net cash used in investing activities	(620,392,000)	(341,161,000)
Financing Activities:
Net proceeds from short-term borrowings from banks	201,000,000	116,300,000
Decrease in securities sold under agreements to repurchase	(56,790,000)	(23,588,000)
Increase in bank deposits, net	497,195,000	346,393,000
Increase in securities loaned	92,518,000	86,091,000
Excess tax benefits from stock-based compensation	25,188,000	14,280,000
Issuance of common stock		865,000
Repurchase of common stock	(48,505,000)	(91,769,000)
Reissuance of treasury stock	2,755,000	2,055,000
EarlyRepayment Of Senior Debt		(23,000,000)
Payment of Federal Home Loan Bank advances		(2,000,000)
Extinguishment of subordinated debt	(1,284,000)	(1,840,000)
Net cash provided by financing activities	712,077,000	423,787,000
Effect of exchange rate changes on cash	(1,261,000)	8,689,000
(Decrease)/increase in cash and cash equivalents	(38,910,000)	45,064,000
Cash and cash equivalents at beginning of period	253,529,000	161,820,000
Cash and cash equivalents at end of period	214,619,000	206,884,000
Supplemental disclosure of cash flow information:
Cash paid for interest	18,880,000	8,539,000
Cash paid for income taxes, net of refunds	5,618,000	51,896,000
Noncash investing and financing activities:
CommonStockIssuanceTWPG		271,285,000
Units, net of forfeitures	$ 119,530,000	$ 137,158,000