Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash Flows From Operating Activities:
Net income	$ 184,859	$ 54,640
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Depreciation and amortization	26,976	31,928
Amortization of loans and advances to financial advisors and other employees	69,393	53,046
Amortization of premium on investment portfolio	11,248	8,561
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	19,025	11,402
Amortization of intangible assets	9,092	10,558
Deferred income taxes	14,875	26,448
Tax deficit from stock-based compensation		5,797
Stock-based compensation	81,613	149,093
(Gains)/losses on sale of investments	(2,888)	3,680
Gain on extinguishment of Stifel Financial Capital Trust		(5,607)
Other, net	2,377	4,479
Decrease/(increase) in operating assets, net of assets acquired:
Cash segregated for regulatory purposes and restricted cash	48,060	226,903
Receivables:
Brokerage clients	125,905	149,744
Brokers, dealers, and clearing organizations	689,648	36,681
Securities purchased under agreements to resell	(209,747)	(137,404)
Financial instruments owned, including those pledged	(139,205)	(399,342)
Loans originated as held for sale	(1,152,654)	(1,919,714)
Proceeds from mortgages held for sale	1,194,709	1,893,352
Loans and advances to financial advisors and other employees	(46,699)	(61,660)
Other assets	(77,373)	(135,030)
Increase/(decrease) in operating liabilities, net of liabilities assumed:
Brokerage clients	(94,594)	(69,064)
Brokers, dealers, and clearing organizations	63,554	(42,812)
Drafts	(17,089)	(123,948)
Financial instruments sold, but not yet purchased	50,291	144,013
Other liabilities and accrued expenses	91,896	(95,292)
Net cash provided by/(used in) operating activities	943,272	(179,548)
Cash Flows From Investing Activities:
Maturities and principal paydowns of available-for-sale securities	850,102	140,453
Calls and principal paydowns of held-to-maturity securities	193,140	163,913
Sale or maturity of investments	25,394	33,615
Disposition of business, net		12,597
Increase in bank loans, net	(1,202,124)	(1,821,877)
Payments for:
Purchase of available-for-sale securities	(1,350,033)	(1,637,419)
Purchase of held-to-maturity securities	(712,450)	(551,984)
Purchase of investments	(1,592)	(9,873)
Purchase of fixed assets	(21,153)	(21,315)
Acquisitions, net of cash received	(6,743)	(71,924)
Net cash used in investing activities	(2,225,459)	(3,763,814)
Cash Flows From Financing Activities:
Proceeds from/(repayments of) borrowings, net	(299,000)	145,116
Proceeds from Federal Home Loan Bank advances, net	290,000	352,000
Payment of contingent consideration	(13,328)
Proceeds from issuance of senior notes, net		201,632
Proceeds from issuance of preferred stock, net		145,275
Decrease in securities sold under agreements to repurchase	(113,150)	(16,940)
Increase in bank deposits, net	1,356,478	3,247,085
Increase/(decrease) in securities loaned	(166,901)	69,055
Tax deficit from stock-based compensation		(5,797)
Restricted stock conversions	(76,242)	(47,507)
Proceeds from stock option exercises		214
Repurchase of common stock	(12,998)	(113,462)
Cash dividends on preferred stock	(7,031)	(1,563)
Cash dividends on common stock	(6,835)
Extinguishment of Stifel Financial Capital Trust		(9,393)
Repayment of senior notes		(150,000)
Net cash provided by financing activities	950,993	3,815,715
Effect of exchange rate changes on cash	7,178	(8,315)
Decrease in cash and cash equivalents	(324,016)	(135,962)
Cash and cash equivalents at beginning of period	912,932	811,019
Cash and cash equivalents at end of period	588,916	675,057
Supplemental disclosure of cash flow information:
Cash paid for income taxes, net of refunds	18,591	22,063
Cash paid for interest	49,901	46,617
Noncash financing activities:
Unit grants, net of forfeitures	55,941	158,345
Issuance of common stock for acquisitions	$ 9,352	$ 11,427