Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash Flows From Operating Activities:
Net income	$ 81,164	$ 130,886
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	27,386	21,727
Amortization of loans and advances to financial advisors and other employees	50,529	49,285
Amortization of premium on investment portfolio	2,557	4,385
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	5,509	6,832
Amortization of intangible assets	5,952	9,762
Deferred income taxes	8,814	17,111
Excess tax benefits from stock-based compensation	(17,031)	(18,220)
Stock-based compensation	110,569	70,852
(Gains)/losses on sale of investments	10,102	(894)
Other, net	278	1,990
Decrease/(increase) in operating assets, net of assets acquired:
Cash segregated for regulatory purposes and restricted cash	49,325	4,264
Receivables:
Brokerage clients	(112,106)	(19,195)
Brokers, dealers, and clearing organizations	33,517	(263,745)
Securities purchased under agreements to resell	(33,389)	99,562
Financial instruments owned, including those pledged	31,484	(139,012)
Loans originated as held for sale	(1,347,547)	(811,711)
Proceeds from mortgages held for sale	1,317,242	808,882
Loans and advances to financial advisors and other employees	(68,468)	(51,492)
Other assets	19,619	42,768
Increase/(decrease) in operating liabilities, net of liabilities assumed:
Brokerage clients	102,353	311
Brokers, dealers, and clearing organizations	50,028	35,297
Drafts	(5,682)	(16,121)
Financial instruments sold, but not yet purchased	(74,942)	131,809
Other liabilities and accrued expenses	(248,703)	(169,588)
Net cash used in operating activities	(1,440)	(54,255)
Cash Flows From Investing Activities:
Maturities, calls, sales, and principal paydowns of available-for-sale securities	853,441	542,565
Calls and principal paydowns of held-to-maturity securities	82,941	74,405
Sale or maturity of investments	52,884	48,278
Sale of other real estate owned	75	131
Increase in bank loans, net	(375,194)	(468,329)
Payments for:
Purchase of available-for-sale securities	(423)	(271,548)
Purchase of held-to-maturity securities		(7,959)
Purchase of investments	(17,086)	(37,190)
Purchase of fixed assets	(61,663)	(22,384)
Acquisitions, net of cash acquired	18,456	(39,184)
Net cash provided by/(used in) investing activities	553,431	(181,215)
Cash Flows From Financing Activities:
Proceeds/(repayments) of borrowings	86,617	(5,900)
Proceeds from Federal Home Loan Bank advances	96,000
Proceeds from issuance of senior notes, net		295,638
Payment of contingent consideration	29,598
Increase/(decrease) in securities sold under agreements to repurchase	67,757	(119,995)
Decrease in bank deposits, net	(673,270)	(110,801)
Increase/(decrease) in securities loaned	42,752	(14,321)
Excess tax benefits from stock-based compensation	17,031	18,220
Issuance of common stock for stock option exercises	343	135
Repurchase of common stock	(65,858)
Repayment of senior notes	(175,000)
Extinguishment of subordinated debt		(3,131)
Net cash provided by/(used in) financing activities	(633,226)	59,845
Effect of exchange rate changes on cash	(1,447)	(5,817)
Decrease in cash and cash equivalents	(82,682)	(181,442)
Cash and cash equivalents at beginning of period	689,782	716,560
Cash and cash equivalents at end of period	607,100	535,118
Supplemental disclosure of cash flow information:
Cash paid for interest	29,673	31,205
Cash paid for income taxes, net of refunds	45,115	59,434
Noncash financing activities:
Unit grants, net of forfeitures	132,145	152,115
Shares surrendered into treasury	223
Issuance of common stock for acquisitions	$ 80,981	$ 11,741