Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash Flows from Operating Activities:
Net income	$ 14,619	$ 34,773
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	7,876	7,189
Amortization of loans and advances to financial advisors and other employees	15,553	13,931
Amortization of premium on available-for-sale securities	(2,989)	2,886
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	1,294	955
Amortization of intangible assets	1,138	1,329
Deferred income taxes	14,846	31,514
Excess tax benefits from stock-based compensation	(8,237)	(12,438)
Stock-based compensation	70,184	6,963
Gains on investments	3,530	(7,952)
Other net	403	(308)
Decrease/(increase) in operating assets:
Cash segregated for regulatory purposes and restricted cash	127,998	299
Receivables:
Brokerage clients	(55,519)	(9,270)
Brokers, dealers and clearing organizations	(177,699)	15,378
Securities purchased under agreements to resell	2,354	(28,503)
Loans originated as held for sale	(437,539)	(100,773)
Proceeds from mortgages held for sale	476,999	(356,192)
Trading securities owned, including those pledged	(39,304)	346,809
Loans and advances to financial advisors and other employees	(12,049)	(25,203)
Other assets	(66,088)	(35,119)
Increase/(decrease) in operating liabilities
Brokerage clients	30,182	45,431
Brokers, dealers and clearing organizations	30,056	13,590
Drafts	(32,118)	(19,274)
Trading securities sold, but not yet purchased	217,385	3,574
Other liabilities and accrued expenses	(126,444)	(119,349)
Net cash used in operating activities	56,431	(189,760)
Cash Flows from Investing Activities:
Maturities, calls, sales, and principal paydowns on available-for-sale securities	68,678	63,783
Calls on held-to-maturity securities	16,289
Sale or maturity of investments	22,380	15,534
Sale of other real estate owned		75
Increase in bank loans, net	(67,585)	(25,534)
Payments for:
Purchase of available-for-sale securities	(185,892)	(192,536)
Purchase of held-to-maturity securities	(16,438)	(136,854)
Purchase of investments	(57,558)	(12,480)
Purchase of fixed assets	(4,931)	(3,902)
Acquisitions	(154,283)
Net cash used in investing activities	(379,340)	(291,914)
Cash Flows from Financing Activities:
(Repayments of)/ proceeds from short-term borrowings from banks	265,100	(12,000)
Proceeds from Senior Note offering		170,291
Increase/(decrease) in securities sold under agreements to repurchase	(31,817)	61,943
Increase in bank deposits, net	210,435	286,174
Increase in securities loaned	46,680	15,936
Excess tax benefits from stock-based compensation	8,237	12,438
Issuance of common stock	15
Repurchase of common stock	297
Reissuance of treasury stock	(3,058)	6,783
Extinguishment of subordinated debt	(2,187)	(1,639)
Net cash provided by financing activities	493,702	539,926
Effect of exchange rate changes on cash	(1,070)	535
Decrease in cash and cash equivalents	169,723	58,787
Cash and cash equivalents at beginning of period	403,941	403,941
Cash and cash equivalents at end of period	573,664	226,458
Supplemental disclosure of cash flow information:
Cash paid for income taxes, net of refunds	15,264	(885)
Cash paid for interest	10,407	6,712
Noncash investing and financing activities:
Units, net of forfeitures	137,694	68,159
Issuance of common stock for acquisitions	$ 265,918