Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows from Operating Activities:
Net income	$ 138,573	$ 84,134	$ 1,907
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	30,066	28,267	23,843
Amortization of loans and advances to financial advisors and other employees	57,147	55,923	50,162
Amortization of premium on available-for-sale securities	16,153	12,782	8,552
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	3,457	2,243	123
Amortization of intangible assets	4,896	5,311	5,518
Deferred income taxes	45,519	25,764	(54,213)
Excess tax benefits from stock-based compensation	(16,722)	(24,863)	(17,487)
Stock-based compensation	40,747	26,411	190,731
Gains on investments	(45,434)	1,877	(5,431)
Other net	(181)	841	3,622
Decrease/(increase) in operating assets:
Cash segregated for regulatory purposes and restricted cash	(125,536)	5,982	(6,004)
Receivables:
Brokerage clients	72,220	(82,210)	(93,765)
Brokers, dealers and clearing organizations	(23,588)	18,395	63,132
Securities purchased under agreements to resell	(83,240)	48,162	1,237
Loans originated as held for sale	(288,657)	(43,467)	25,316
Proceeds from mortgages held for sale	(1,603,074)	(1,060,457)	(1,130,528)
Trading securities owned, including those pledged	1,517,458	1,013,515	1,104,317
Loans and advances to financial advisors and other employees	(63,948)	(46,426)	(46,376)
Other assets	8,476	14,842	22,473
Increase/(decrease) in operating liabilities
Brokerage clients	49,623	33,244	(2,241)
Brokers, dealers and clearing organizations	(1,492)	(72,495)	13,251
Drafts	14,532	2,653	6,284
Trading securities sold, but not yet purchased	56,652	65,296	(77,230)
Other liabilities and accrued expenses	(67,914)	(70,310)	54,295
Net cash used in operating activities	(264,267)	45,414	141,488
Cash Flows from Investing Activities:
Maturities, calls, sales, and principal paydowns on available-for-sale securities	530,120	654,958	309,646
Calls on held-to-maturity securities	15,464	9,450
Sale or maturity of investments	105,077	76,263	105,703
Sale of bank branch			13,905
Sale of other real estate owned	221	929	2,099
Increase in bank loans, net	(180,115)	(243,592)	(55,214)
Payments for:
Purchase of available-for-sale securities	(945,343)	(895,391)	(747,376)
Purchase of held-to-maturity securities	(531,379)	(119,960)	(45,963)
Purchase of investments	(80,887)	(119,720)	(121,885)
Purchase of fixed assets	(18,837)	(59,730)	(27,736)
Acquisitions	(120,180)	(18,817)	(483)
Net cash used in investing activities	(1,225,859)	(715,610)	(567,304)
Cash Flows from Financing Activities:
(Repayments of)/ proceeds from short-term borrowings from banks	105,300	89,800	18,800
Proceeds from Senior Note offering	316,380
Proceeds from issuance of senior notes, net	58,992
Increase/(decrease) in securities sold under agreements to repurchase	60,170	(29,419)	(12,938)
Increase in bank deposits, net	1,274,395	448,170	593,977
Increase in securities loaned	(105,208)	97,537	11,158
Excess tax benefits from stock-based compensation	16,722	24,863	17,487
Issuance of common stock	41		865
Repurchase of common stock	(11,380)	(48,505)	(91,769)
Reissuance of treasury stock	11,562	3,983	5,045
Extinguishment of senior notes			(23,000)
Repayments of Federal Home Loan Bank advances			(2,000)
Extinguishment of subordinated debt	(1,639)	(1,284)	(1,840)
Net cash provided by financing activities	1,725,335	585,145	515,785
Effect of exchange rate changes on cash	1,061	(807)	1,740
Decrease in cash and cash equivalents	236,270	(85,858)	91,709
Cash and cash equivalents at beginning of period	167,671	253,529	161,820
Cash and cash equivalents at end of period	403,941	167,671	253,529
Supplemental disclosure of cash flow information:
Cash paid for income taxes, net of refunds	4,630	5,547	54,984
Cash paid for interest		25,209	13,104
Noncash investing and financing activities:
Units, net of forfeitures	145,563	138,203	157,546
Issuance of common stock for acquisitions	$ 21,750	$ 6,100	$ 271,285