Stifel Financial (SF) 10-Q 6 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 01, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Trading Symbol	SF
Entity Registrant Name	STIFEL FINANCIAL CORP
Entity Central Index Key	720,672
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		72,011,806

Consolidated Statements Of Fina

Consolidated Statements Of Financial Condition - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Assets
Cash and cash equivalents		$ 694,302	$ 696,283
Cash segregated for regulatory purposes		21,585	90,802
Receivables:
Brokerage clients, net		1,466,664	1,384,096
Brokers, dealers, and clearing organizations		646,120	459,107
Securities purchased under agreements to resell	[1]	622,361	512,220
Financial instruments owned, at fair value		1,162,732	1,143,684
Available-for-sale securities, at fair value		3,349,607	3,773,508
Held-to-maturity securities, at amortized cost	[2]	4,565,453	3,698,098
Loans held for sale, at lower of cost or market		262,063	226,068
Bank loans, net		8,253,989	6,947,759
Investments, at fair value		79,170	111,379
Fixed assets, net		297,846	155,120
Goodwill		1,025,714	968,834
Intangible assets, net		118,923	109,627
Loans and advances to financial advisors and other employees, net		383,477	378,124
Deferred tax assets, net		116,880	105,152
Other assets		693,162	624,092
Total Assets		23,760,048	21,383,953
Payables:
Brokerage clients		627,745	828,206
Brokers, dealers, and clearing organizations		928,132	276,302
Drafts		91,639	107,043
Securities sold under agreements to repurchase	[3]	495,484	233,704
Bank deposits		14,502,952	13,411,935
Financial instruments sold, but not yet purchased, at fair value		911,374	778,863
Accrued compensation		379,453	493,973
Accounts payable and accrued expenses		374,456	308,911
Federal Home Loan Bank advances		1,064,000	745,000
Borrowings		140,030	256,000
Senior notes		1,015,714	1,014,940
Debentures to Stifel Financial Capital Trusts		67,500	67,500
Total liabilities		20,598,479	18,522,377
Shareholders’ Equity:
Preferred stock - $1 par value; authorized 3,000,000 shares; 6,000 shares issued		150,000	150,000
Common stock - $0.15 par value; authorized 97,000,000 shares; issued 74,441,001 and 71,636,986 shares, respectively		11,166	10,746
Additional paid-in-capital		1,873,232	1,733,348
Retained earnings		1,265,536	1,033,526
Accumulated other comprehensive loss		(59,389)	(26,736)
Stockholders' Equity before adjustment for Treasury Stock		3,240,545	2,900,884
Treasury stock, at cost, 1,435,882 and 772,302 shares, respectively		(78,976)	(39,308)
Total Shareholders’ Equity		3,161,569	2,861,576
Total Liabilities and Shareholders’ Equity		$ 23,760,048	$ 21,383,953
[1]	Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.
[3]	Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Consolidated Statements Of Fi_2

Consolidated Statements Of Financial Condition (Parenthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	3,000,000	3,000,000
Preferred stock, shares issued	6,000	6,000
Common stock, par value	$ 0.15	$ 0.15
Common stock, shares authorized	97,000,000	97,000,000
Common stock, shares issued	74,441,001	71,636,986
Treasury stock, shares	1,435,882	772,302

Consolidated Statements Of Oper

Consolidated Statements Of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017
Revenues:
Revenue from contracts with customers	[1]	$ 532,144			$ 1,605,149
Principal transactions		83,152		$ 87,010	269,918		$ 299,570
Interest		169,760		117,862	461,915		327,766
Other income		6,127		9,558	18,557		25,508
Total revenues		786,810		738,794	2,343,632		2,172,512
Interest expense		48,468		17,625	112,200		50,165
Net revenues	[2]	738,342		721,169	2,231,432		2,122,347
Non-interest expenses:
Compensation and benefits		422,324		448,410	1,322,387		1,338,673
Occupancy and equipment rental		54,035		57,427	165,226		167,864
Communications and office supplies		33,330		34,650	103,468		102,686
Commissions and floor brokerage		11,338		11,232	30,798		33,187
Other operating expenses		76,785		61,311	231,122		209,581
Total non-interest expenses		597,812		613,030	1,853,001		1,851,991
Income from operations before income tax expense		140,530		108,139	378,431		270,356
Provision for income taxes		36,672		41,603	98,525		85,497
Net income		103,858		66,536	279,906		184,859
Preferred dividends		2,343		2,343	7,031		7,031
Net income available to common shareholders		$ 101,515		$ 64,193	$ 272,875		$ 177,828
Earnings per common share:
Basic		$ 1.41		$ 0.94	$ 3.80		$ 2.60
Diluted		$ 1.25		$ 0.79	$ 3.35		$ 2.21
Weighted-average number of common shares outstanding:
Basic		71,919		68,522	71,824		68,488
Diluted		81,484		80,881	81,425		80,562
Cash dividends declared per common share		$ 0.12		$ 0.10	$ 0.36		$ 0.10
Commissions [Member]
Revenues:
Revenue from contracts with customers		$ 158,016		$ 162,612	$ 490,693		$ 510,150
Investment Banking [Member]
Revenues:
Revenue from contracts with customers		169,012		181,904	506,437		494,017
Asset Management and Service Fees [Member]
Revenues:
Revenue from contracts with customers		$ 200,743	[1]	$ 179,848	$ 596,112	[1]	$ 515,501
[1]	Excludes revenue included in the Other segment.
[2]	No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2018 or 2017.

Consolidated Statements Of Comp

Consolidated Statements Of Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net income		$ 103,858	$ 66,536	$ 279,906	$ 184,859
Other comprehensive income/(loss), net of tax:
Changes in unrealized gains/(losses) on available-for-sale securities	[1],[2],[3]	(3,138)	4,736	(28,065)	12,283
Amortization of losses of securities transferred to held-to-maturity from available-for-sale	[1],[2]		439		1,348
Changes in unrealized gains/(losses) on cash flow hedging instruments	[1],[2],[4]	(1,523)	183	1,895	698
Foreign currency translation adjustment	[1],[2]	(1,336)	2,644	(3,434)	7,178
Total other comprehensive income/(loss), net of tax	[1],[2]	(5,997)	8,002	(29,604)	21,507
Comprehensive income		$ 97,861	$ 74,538	$ 250,302	$ 206,366
[1]	Net of tax benefit of $2.1 million and tax expense of $5.0 million for the three months ended September 30, 2018 and 2017, respectively. Net of tax benefit of $10.4 million and tax expense of $13.5 million for the nine months ended September 30, 2018 and 2017, respectively.
[2]	The adoption of ASU 2018-02 on January 1, 2018 resulted in a reclassification of $3.0 million to retained earnings related to cash flow hedges and investment portfolio risk. The reclassification is reflected in the activity for the nine months ended September 30, 2018. See Note 2 for further details.
[3]	There were no reclassifications to earnings during the three and nine months ended September 30, 2018 and 2017, respectively.
[4]	Amounts are net of reclassifications to earnings of gains of $1.5 million and $0.7 million for the three months ended September 30, 2018 and 2017, respectively. Amounts are net of reclassifications to earnings of gains of $3.3 million and losses of $0.8 million for the nine months ended September 30, 2018 and 2017, respectively.

Consolidated Statements Of Co_2

Consolidated Statements Of Comprehensive Income (Parenthetical) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Other comprehensive income/(loss), tax	$ 2,100	$ 5,000	$ 10,400	$ 13,500
Reclassifications to earnings of realized gains on available-for-sale securities	0	0	0	0
Reclassifications to earnings of gains/(losses) on cash flow hedging instruments	$ 1,500	$ 700	3,300	$ (800)
ASU 2018-02 [Member]
Reclassification to retained earnings related to cash flow hedges and investment portfolio credit risk			$ 3,000

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows From Operating Activities:
Net income	$ 279,906	$ 184,859
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Depreciation and amortization	20,503	26,976
Amortization of loans and advances to financial advisors and other employees	61,783	69,393
Amortization of premium on investment portfolio	18,714	11,248
Provision for loan losses and allowance for loans and advances to financial advisors and other employees	13,980	19,025
Amortization of intangible assets	8,741	9,092
Deferred income taxes	718	14,875
Stock-based compensation	75,382	81,613
(Gains)/losses on sale of investments	10,442	(2,888)
Other, net	(86,576)	2,377
Receivables:
Brokerage clients	(82,568)	125,905
Brokers, dealers, and clearing organizations	(187,013)	689,648
Securities purchased under agreements to resell	(110,141)	(209,747)
Financial instruments owned, including those pledged	(19,048)	(139,205)
Loans originated as held for sale	(1,099,187)	(1,152,654)
Proceeds from mortgages held for sale	1,051,789	1,194,709
Loans and advances to financial advisors and other employees	(67,872)	(46,699)
Other assets	31,543	(77,373)
Increase/(decrease) in operating liabilities, net of liabilities assumed:
Brokerage clients	(200,461)	(94,594)
Brokers, dealers, and clearing organizations	180,463	63,554
Drafts	(15,404)	(17,089)
Financial instruments sold, but not yet purchased	132,511	50,291
Other liabilities and accrued expenses	(66,290)	91,896
Net cash provided by/(used in) operating activities	(48,085)	895,212
Cash Flows From Investing Activities:
Maturities and principal paydowns of available-for-sale securities	763,982	850,102
Calls and principal paydowns of held-to-maturity securities	443,295	193,140
Sale or maturity of investments	24,345	25,394
Increase in bank loans, net	(810,798)	(1,202,124)
Payments for:
Purchase of available-for-sale securities	(331,657)	(1,350,033)
Purchase of held-to-maturity securities	(1,313,587)	(712,450)
Purchase of investments	(7,578)	(1,592)
Purchase of fixed assets	(18,271)	(21,153)
Acquisitions, net of cash received	599	(6,743)
Net cash used in investing activities	(1,249,670)	(2,225,459)
Cash Flows From Financing Activities:
Repayments of borrowings, net	(257,197)	(299,000)
Proceeds from Federal Home Loan Bank advances, net	309,050	290,000
Payment of contingent consideration	(11,909)	(13,328)
Increase/(decrease) in securities sold under agreements to repurchase	261,780	(113,150)
Increase in bank deposits, net	590,000	1,356,478
Increase/(decrease) in securities loaned	471,367	(166,901)
Tax payments related to shares withheld for stock-based compensation plans	(39,815)	(76,242)
Proceeds from stock option exercises	2,278
Repurchase of common stock	(62,514)	(12,998)
Cash dividends on preferred stock	(7,031)	(7,031)
Cash dividends paid to common stock and equity-award holders	(26,023)	(6,835)
Net cash provided by financing activities	1,229,986	950,993
Effect of exchange rate changes on cash	(3,429)	7,178
Decrease in cash, cash equivalents, and cash segregated for regulatory purposes	(71,198)	(372,076)
Cash, cash equivalents, and cash segregated for regulatory purposes at beginning of period	787,085	986,167
Cash, cash equivalents, and cash segregated for regulatory purposes at end of period	715,887	614,091
Supplemental disclosure of cash flow information:
Cash paid for income taxes, net of refunds	27,280	18,591
Cash paid for interest	111,832	49,901
Noncash financing activities:
Unit grants, net of forfeitures	119,051	55,941
Issuance of common stock for acquisitions	$ 110,671	$ 9,352

Cash, Cash Equivalents, and Cas

Cash, Cash Equivalents, and Cash Restricted for Regulatory Purposes for Periods Presented in Consolidated Statement of Financial Condition - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Statement Of Cash Flows [Abstract]
Cash and cash equivalents	$ 694,302	$ 696,283	$ 588,916
Cash segregated for regulatory purposes	21,585	90,802	25,175
Total cash, cash equivalents, and cash segregated for regulatory purposes	$ 715,887	$ 787,085	$ 614,091

Nature of Operations And Basis

Nature of Operations And Basis of Presentation	9 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Operations, Basis of Presentation, and Summary of Significant Accounting Policies	NOTE 1 – Nature of Operations, Basis of Presentation, and Summary of Significant Accounting Policies Nature of Operations Stifel Financial Corp. (the “Company”), through its wholly owned subsidiaries, is principally engaged in retail brokerage; securities trading; investment banking; investment advisory; retail, consumer, and commercial banking; and related financial services. We have offices throughout the United States and Europe. Our major geographic area of concentration is throughout the United States, with a growing presence in the United Kingdom and Europe. Our company’s principal customers are individual investors, corporations, municipalities, and institutions. On March 19, 2018, the Company completed the acquisition of Ziegler Wealth Management (“Ziegler”), a privately held investment bank, capital markets and proprietary investments firm that has 55 private client advisors in five states that manage approximately $5 billion in client assets. Ziegler provides its clients with capital raising, strategic advisory services, equity and fixed income sales & trading and research. The acquisition was funded with cash from operations. See Note 8 in the notes to consolidated financial statements for more details. On August 31, 2018, the Company completed the acquisition of Business Bancshares, Inc. (“BBI”) and its wholly owned subsidiary, The Business Bank of St. Louis, a full-service banking facility with approximately $600.0 million in assets that operates from a single location. Upon the closing of the transaction, the Business Bank of St. Louis was renamed “Stifel Bank” and Business Bancshares, Inc. was renamed “Stifel Bancorp, Inc.” Stifel Bancorp, Inc. (“Stifel Bancorp”) is the holding company for Stifel Bank & Trust, Stifel Bank, and their wholly owned subsidiaries. We issued approximately 2.0 million shares for acquisition of BBI. See Note 8 in the notes to consolidated financial statements for more details. Pro forma information is not presented, because the acquisition is not considered to be material, as defined by the SEC. The results of operations of Ziegler and Stifel Bancorp have been included in our results prospectively from the date of acquisition. Basis of Presentation The consolidated financial statements include Stifel Financial Corp. and its wholly owned subsidiaries, principally Stifel, Nicolaus & Company, Incorporated (“Stifel”), Keefe, Bruyette & Woods, Inc., and Stifel Bancorp. All material intercompany balances and transactions have been eliminated. Unless otherwise indicated, the terms “we,” “us,” “our,” or “our company” in this report refer to Stifel Financial Corp. and its wholly owned subsidiaries. We have prepared the accompanying unaudited consolidated financial statements pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Pursuant to these rules and regulations, we have omitted certain information and footnote disclosures we normally include in our annual consolidated financial statements prepared in accordance with U.S. generally accepted accounting principles. In management’s opinion, we have made all adjustments (consisting only of normal, recurring adjustments, except as otherwise noted) necessary to fairly present our financial position, results of operations and cash flows. Our interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. These financial statements and accompanying notes should be read in conjunction with the consolidated financial statements and the notes thereto in our Annual Report on Form 10-K for the year ended December 31, 2017 on file with the SEC. Certain amounts from prior periods have been reclassified to conform to the current period’s presentation. The effect of these reclassifications on our company’s previously reported consolidated financial statements was not material. Summary of Significant Accounting Policies For a detailed discussion about the Company’s significant accounting policies, see Note 2, Summary of Significant Accounting Policies, in our consolidated financial statements included in Part II, Item 8 of our Annual Report on Form 10-K for the year ended December 31, 2017. Other than the following, there were no significant changes made to the Company’s significant accounting policies. The accounting policy changes are attributable to the adoption of the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (the “new revenue standard” or “ASU 2014-09”) on January 1, 2018. These revenue recognition policy updates are applied prospectively in our consolidated financial statements from January 1, 2018. Reported financial information for the historical comparable period was not revised and continues to be reported under the accounting standards in effect during the historical periods. The new revenue standard primarily impacts the following revenue recognition and presentation accounting policies of our company: Investment Banking Revenues Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Advisory expenses are deferred only to the extent they are explicitly reimbursable by the client and the related revenue is recognized at a point in time. All other investment banking advisory related expenses are expensed as incurred. Underwriting expenses are recognized as non-interest expense in the consolidated statements of operations and any expense reimbursements are recognized as investment banking revenues. See Note 2, New Accounting Pronouncements, and Note 17, Revenues from Contracts with Customers, for further information.

New Accounting Pronouncements

New Accounting Pronouncements	9 Months Ended
	Sep. 30, 2018
Prospective Adoption Of New Accounting Pronouncements [Abstract]
New Accounting Pronouncements	NOTE 2 – New Accounting Pronouncements Recently Adopted Accounting Guidance Comprehensive Income In February 2018, the FASB issued ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” that provides for the reclassification from accumulated other comprehensive income to retained earnings for stranded effects resulting from the Tax Cuts and Jobs Act of 2017. The accounting update is effective for fiscal years beginning after December 15, 2018 and early adoption is permitted. We early adopted the guidance in the update on January 1, 2018. The adoption of the accounting update resulted in a reclassification adjustment of $3.0 million related to cash flow hedges and investment portfolio credit risk in our consolidated financial statements. Statement of Cash Flows In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230) – Restricted Cash,” which adds or clarifies guidance on the classification and presentation of restricted cash in the statement of cash flows. The accounting update is effective for fiscal years beginning after December 15, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated statement of cash flows. Upon adoption of the accounting update, we recorded a decrease of $48.1 million in net cash provided by operating activities for the nine months ended September 30, 2017 related to reclassifying the changes in our cash segregated for regulatory purposes and restricted cash balance from operating activities to the cash and cash equivalent balances within the consolidated statements of cash flows. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230) – Classification of Certain Cash Receipts and Cash Payments,” which amends and clarifies the current guidance to reduce diversity in practice of the classification of certain cash receipts and payments in the consolidated statements of cash flows. The accounting update is effective for fiscal years beginning after December 31, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated statements of cash flows. Financial Assets and Financial Liabilities In January 2016, the FASB issued ASU 2016-01, “Financial Instruments – Recognition and Measurement of Financial Assets and Financial Liabilities” that will change the income statement impact of equity investments held by an entity, and the recognition of changes in fair value of financial liabilities when the fair value option is elected. The accounting update also amends certain disclosure requirements associated with the fair value of financial instruments. The accounting update is effective for fiscal years beginning after December 15, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated financial statements. Revenue Recognition Effective January 1, 2018, the Company adopted ASU 2014-09, which provides accounting guidance on the recognition of revenues from contracts and requires gross presentation of certain costs that were previously offset against revenue. This change was applied prospectively from January 1, 2018 and there is no impact on our previously presented results. The adoption of the new revenue standard resulted in a reduction of beginning retained earnings of $3.9 million after-tax as a cumulative effect of adoption of an accounting change. The impact of adoption is primarily related to investment banking revenues that were previously recognized in prior periods, which are now being deferred under the new revenue standard. With the adoption of the new revenue recognition standard on January 1, 2018, capital raising and advisory fee revenues are no longer presented net of the related out-of-pocket deal expenses. As a result, capital raising and advisory fee revenues and other operating expenses are higher in the first nine months of 2018 by an identical $25.9 million, with no impact to net income. The scope of the accounting update does not apply to revenue associated with financial instruments, and as a result, will not have an impact on the elements of our consolidated statements of operations most closely associated with financial instruments, including principal transaction revenues, interest income, and interest expense. The new revenue standard primarily impacts the following revenue recognition and presentation accounting policies: Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Advisory expenses had historically been deferred until reimbursed by the client, the related fee revenue was recognized or the engagement was otherwise concluded. Under the new revenue standard, expenses are deferred only to the extent they are explicitly reimbursable by the client and the related revenue has been recognized. All other investment banking advisory related expenses, including expenses incurred related to restructuring assignments, are expensed as incurred. Underwriting expenses had historically been recorded net of client reimbursements and/or netted against revenues. Under the new revenue standard, all investment banking expenses will be recognized as non-interest expense in the consolidated statements of operations and any expense reimbursements will be recognized as investment banking revenues (i.e., expenses are no longer recorded net of client reimbursements and are not netted against revenues). Recently Issued Accounting Guidance Derivatives and Hedging In August 2017, the FASB issued ASU 2017-12, “Derivatives and Hedging (Topic 815) – Targeted Improvements to Accounting for Hedging Activities,” which amends the hedge accounting recognition and presentation requirements. The accounting update improves the transparency and understandability of information conveyed to financial statement users by better aligning companies’ hedging relationship to their existing risk management strategies, simplifies the application of hedge accounting and increases transparency regarding the scope and results of hedging program. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) and early adoption is permitted. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Callable Debt Securities In March 2017, the FASB issued ASU 2017-08, “Receivables – Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities,” which shortens the amortization period for the premium on certain callable debt securities to the earliest call date. The amendments are applicable to any purchased individual debt security with an explicit and non-contingent call feature that is callable at a fixed price on a preset date. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) under a modified retrospective approach and early adoption is permitted. We are evaluating the impact the adoption of this new guidance will have on our consolidated financial statements. Goodwill Impairment Testing In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,” which simplifies the subsequent measurement of goodwill and eliminates Step 2 from the goodwill impairment test. Under the accounting update, the annual, or interim, goodwill impairment test is performed by comparing the fair value of a reporting unit with its carrying amount, and an impairment charge should be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The accounting update is effective for annual or any interim impairment tests in fiscal years beginning after December 15, 2019 (January 1, 2020 for our company) and early adoption is permitted. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Financial Instruments – Credit Losses In June 2016, the FASB issued ASU 2016-13, “Financial Instruments − Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” This accounting update impacts the impairment model for certain financial assets measured at amortized cost by requiring a current expected credit loss (“CECL”) methodology to estimate expected credit losses over the entire life of the financial asset, recorded at inception or purchase. CECL will replace the loss model currently applicable to bank loans, held-to-maturity securities, and other receivables carried at amortized cost. The accounting update also eliminates the concept of other-than-temporary impairment for available-for-sale securities. Impairments on available-for-sale securities will be required to be recognized in earnings through an allowance, when the fair value is less than amortized cost and a credit loss exists or the securities are expected to be sold before recovery of amortized cost. Under the accounting update, there may be an ability to determine there are no expected credit losses in certain circumstances, e.g., based on collateral arrangements for lending and financing transactions or based on the credit quality of the borrower or issuer. Overall, the amendments in this accounting update are expected to accelerate the recognition of credit losses for portfolios where CECL models will be applied. The accounting update is effective for fiscal years beginning after December 15, 2019 (January 1, 2020 for our company) with early adoption permitted as of January 1, 2019. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Leases In February 2016, the FASB issued ASU 2016-02, “Leases – (Topic 842)” that requires for leases longer than one year, a lessee recognize in the statements of financial condition a right-of-use asset, representing the right to use the underlying asset for the lease term, and a lease liability, representing the liability to make lease payments. The accounting update also requires that for finance leases, a lessee recognize interest expense on the lease liability, separately from the amortization of the right-of-use asset in the statements of earnings, while for operating leases, such amounts should be recognized as a combined expense. In addition, this accounting update requires expanded disclosures about the nature and terms of lease agreements. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) under a modified retrospective approach and early adoption is permitted. The Company’s implementation efforts include reviewing existing leases and service contracts, which may include embedded leases. Upon adoption, our company expects a gross up on its consolidated statements of financial condition upon recognition of the right-of-use assets and lease liabilities and does not expect the amount of the gross up to have a material impact on its financial condition.

Receivables From And Payables T

Receivables From And Payables To Brokers, Dealers And Clearing Organizations	9 Months Ended
	Sep. 30, 2018
Due To And From Broker Dealers And Clearing Organizations [Abstract]
Receivables From And Payables To Brokers, Dealers And Clearing Organizations	NOTE 3 – Receivables From and Payables to Brokers, Dealers, and Clearing Organizations Amounts receivable from brokers, dealers, and clearing organizations at September 30, 2018 and December 31, 2017, included (in thousands) September 30, 2018 December 31, 2017 Receivables from clearing organizations $ 440,154 $ 270,285 Deposits paid for securities borrowed 170,165 132,776 Securities failed to deliver 35,801 56,046 $ 646,120 $ 459,107 Amounts payable to brokers, dealers, and clearing organizations at September 30, 2018 and December 31, 2017, included (in thousands) September 30, 2018 December 31, 2017 Deposits received from securities loaned $ 691,150 $ 219,782 Payable to clearing organizations 201,510 27,223 Securities failed to receive 35,472 29,297 $ 928,132 $ 276,302 Deposits paid for securities borrowed approximate the market value of the securities. Securities failed to deliver and receive represent the contract value of securities that have not been delivered or received on settlement date.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE 4 – Fair Value Measurements We measure certain financial assets and liabilities at fair value on a recurring basis, including financial instruments owned, available-for-sale securities, investments, financial instruments sold, but not yet purchased, and derivatives. We generally utilize third-party pricing services to value Level 1 and Level 2 available-for-sale investment securities, as well as certain derivatives designated as cash flow hedges. We review the methodologies and assumptions used by the third-party pricing services and evaluate the values provided, principally by comparison with other available market quotes for similar instruments and/or analysis based on internal models using available third-party market data. We may occasionally adjust certain values provided by the third-party pricing service when we believe, as the result of our review, that the adjusted price most appropriately reflects the fair value of the particular security. Following are descriptions of the valuation methodologies and key inputs used to measure financial assets and liabilities recorded at fair value. The descriptions include an indication of the level of the fair value hierarchy in which the assets or liabilities are classified. Financial Instruments Owned and Available-For-Sale Securities When available, the fair value of financial instruments is based on quoted prices in active markets and reported in Level 1. Level 1 financial instruments include highly liquid instruments with quoted prices, such as equity securities listed in active markets, corporate fixed income securities, U.S. government securities, and U.S. government agency securities. If quoted prices are not available for identical instruments, fair values are obtained from pricing services, broker quotes, or other model-based valuation techniques with observable inputs, such as the present value of estimated cash flows, and reported as Level 2. The nature of these financial instruments include instruments for which quoted prices are available but traded less frequently, instruments whose fair value has been derived using a model where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data, and instruments that are fair valued using other financial instruments, the parameters of which can be directly observed. Level 2 financial instruments include U.S. government agency securities, mortgage-backed securities, corporate fixed income and equity securities infrequently traded, state and municipal securities, sovereign debt, and asset-backed securities, which primarily include collateralized loan obligations. We have identified Level 3 financial instruments to include certain equity securities with unobservable pricing inputs and certain non-agency mortgage-backed securities. Level 3 financial instruments have little to no pricing observability as of the report date. These financial instruments do not have active two-way markets and are measured using management’s best estimate of fair value, where the inputs into the determination of fair value require significant management judgment or estimation. Investments Investments carried at fair value primarily include corporate equity securities, auction-rate securities (“ARS”), and private company investments. Corporate equity securities are valued based on quoted prices in active markets and reported in Level 1. No securities with unobservable pricing inputs are reported in Level 3. ARS are valued based upon our expectations of issuer redemptions and using internal discounted cash flow models that utilize unobservable inputs. ARS are reported as Level 3 assets. Direct investments in private companies, reported as Level 3 assets, may be valued using the market approach and were valued based on an assessment of each underlying investment, incorporating evaluation of additional significant third-party financing, changes in valuations of comparable peer companies, the business environment of the companies, market indices, assumptions relating to appropriate risk adjustments for nonperformance, and legal restrictions on disposition, among other factors. The fair value derived from the methods used are evaluated and weighted, as appropriate, considering the reasonableness of the range of values indicated. Under the market approach, fair value may be determined by reference to multiples of market-comparable companies or transactions, including earnings before interest, taxes, depreciation, and amortization (“EBITDA”) multiples. For securities utilizing the market comparable companies valuation technique, a significant increase (decrease) in the EBITDA multiple in isolation could result in a significantly higher (lower) fair value measurement. Investments in Funds That Are Measured at Net Asset Value Per Share The Company’s investments in funds measured at NAV include private company investments, partnership interests, mutual funds, private equity funds, and money market funds. Private equity funds primarily invest in a broad range of industries worldwide in a variety of situations, including leveraged buyouts, recapitalizations, growth investments and distressed investments. The private equity funds are primarily closed-end funds in which the Company’s investments are generally not eligible for redemption. Distributions will be received from these funds as the underlying assets are liquidated or distributed. The general and limited partnership interests in investment partnerships were primarily valued based upon NAVs received from third-party fund managers. The various partnerships are investment companies, which record their underlying investments at fair value based on fair value policies established by management of the underlying fund. Fair value policies at the underlying fund generally require the funds to utilize pricing/valuation information, including independent appraisals, from third-party sources. However, in some instances, current valuation information for illiquid securities or securities in markets that are not active may not be available from any third-party source or fund management may conclude that the valuations that are available from third-party sources are not reliable. In these instances, fund management may perform model-based analytical valuations that may be used as an input to value these investments. The tables below present the fair value of our investments in, and unfunded commitments to, funds that are measured at NAV (in thousands): September 30, 2018 Fair value of investments Unfunded commitments Money market funds $ 18,696 $ — Mutual funds 10,506 — Private equity funds 3,394 1,535 Partnership interests 4,405 1,324 Total $ 37,001 $ 2,859 December 31, 2017 Fair value of investments Unfunded commitments Money market funds $ 77,441 $ — Mutual funds 11,748 — Private equity funds 7,677 1,825 Partnership interests 5,124 1,330 Total $ 101,990 $ 3,155 Financial Instruments Sold, But Not Yet Purchased Financial instruments sold, but not purchased, recorded at fair value based on quoted prices in active markets and other observable market data include highly liquid instruments with quoted prices, such as U.S. government securities, corporate fixed income securities, and equity securities listed in active markets, which are reported as Level 1. If quoted prices are not available, fair values are obtained from pricing services, broker quotes, or other model-based valuation techniques with observable inputs, such as the present value of estimated cash flows, and reported as Level 2. The nature of these financial instruments include instruments for which quoted prices are available but traded less frequently, instruments whose fair value has been derived using a model where inputs to the model are directly observable in the market, or can be derived principally from or corroborated by observable market data, and instruments that are fair valued using other financial instruments, the parameters of which can be directly observed. Level 2 financial instruments include U.S. government agency securities, mortgage-backed securities not actively traded, corporate fixed income securities, and sovereign debt. Derivatives Derivatives are valued using quoted market prices for identical instruments when available or pricing models based on the net present value of estimated future cash flows. The valuation models used require market observable inputs, including contractual terms, market prices, yield curves, credit curves, and measures of volatility. We manage credit risk for our derivative positions on a counterparty-by-counterparty basis and calculate credit valuation adjustments, included in the fair value of these instruments, on the basis of our relationships at the counterparty portfolio/master netting agreement level. These credit valuation adjustments are determined by applying a credit spread for the counterparty to the total expected exposure of the derivative after considering collateral and other master netting arrangements. We have classified our interest rate swaps as Level 2. Assets and liabilities measured at fair value on a recurring basis as of September 30, 2018, are presented below (in thousands) September 30, 2018 Total Level 1 Level 2 Level 3 Financial instruments owned: U.S. government securities $ 36,214 $ 36,214 $ — $ — U.S. government agency securities 167,886 — 167,886 — Mortgage-backed securities: Agency 380,044 — 380,044 — Non-agency 23,747 — 23,746 1 Asset-backed securities 29,806 — 29,451 355 Corporate securities: Fixed income securities 290,627 262 290,365 — Equity securities 69,205 68,892 212 101 Sovereign debt 15,996 — 15,996 — State and municipal securities 149,207 — 149,207 — Total financial instruments owned 1,162,732 105,368 1,056,907 457 Available-for-sale securities: U.S. government agency securities 5,165 516 4,649 — State and municipal securities 68,876 — 68,876 — Mortgage-backed securities: Agency 250,808 — 250,808 — Commercial 68,823 — 68,823 — Non-agency 1,269 — 1,269 — Corporate fixed income securities 1,177,315 — 1,177,315 — Asset-backed securities 1,777,351 — 1,777,351 — Total available-for-sale securities 3,349,607 516 3,349,091 — Investments: Corporate equity securities 42,495 42,495 — — Auction rate securities: Equity securities 16,525 — — 16,525 Municipal securities 799 — — 799 Other 1,046 — 189 857 Investments in funds measured at NAV 18,305 Total investments 79,170 42,495 189 18,181 Cash equivalents measured at NAV 18,696 Derivative contracts (1) 11,117 11,117 $ 4,621,322 $ 148,379 $ 4,417,304 $ 18,638 (1) September 30, 2018 Total Level 1 Level 2 Level 3 Liabilities: Financial instruments sold, but not yet purchased: U.S. government securities $ 512,275 $ 512,275 $ — $ — Mortgage-backed securities: Agency 95,312 — 95,312 — Corporate securities: Fixed income securities 213,335 96 213,239 — Equity securities 78,895 78,895 — — Sovereign debt 11,557 — 11,557 — Total financial instruments sold, but not yet purchased $ 911,374 $ 591,266 $ 320,108 $ — Assets and liabilities measured at fair value on a recurring basis as of December 31, 2017, are presented below (in thousands) December 31, 2017 Total Level 1 Level 2 Level 3 Financial instruments owned: U.S. government securities $ 13,466 $ 13,466 $ — $ — U.S. government agency securities 147,223 — 147,223 — Mortgage-backed securities: Agency 302,445 — 302,445 — Non-agency 29,356 — 29,355 1 Asset-backed securities 76,752 — 76,395 357 Corporate securities: Fixed income securities 325,471 362 324,867 242 Equity securities 46,802 46,411 138 253 Sovereign debt 32,470 — 32,470 — State and municipal securities 169,699 — 169,699 — Total financial instruments owned 1,143,684 60,239 1,082,592 853 Available-for-sale securities: U.S. government agency securities 4,983 516 4,467 — State and municipal securities 70,559 — 70,559 — Mortgage-backed securities: Agency 305,530 — 305,530 — Commercial 72,488 — 72,488 — Non-agency 1,568 — 1,568 — Corporate fixed income securities 1,211,442 — 1,211,442 — Asset-backed securities 2,106,938 — 2,106,938 — Total available-for-sale securities 3,773,508 516 3,772,992 — Investments: Corporate equity securities 49,978 49,978 — — Auction rate securities: Equity securities 34,789 — — 34,789 Municipal securities 846 — — 846 Other 1,217 — 360 857 Investments measured at NAV 24,549 Total investments 111,379 49,978 360 36,492 Cash equivalents measured at NAV 77,441 Derivative contracts (1) 7,995 — 7,995 — $ 5,114,007 $ 110,733 $ 4,863,939 $ 37,345 (1) December 31, 2017 Total Level 1 Level 2 Level 3 Liabilities: Financial instruments sold, but not yet purchased: U.S. government securities $ 442,402 $ 442,402 $ — $ — U.S. government agency securities 10,348 — 10,348 — Mortgage-backed securities: Agency 86,612 — 86,612 — Corporate securities: Fixed income securities 180,755 — 180,755 — Equity securities 38,510 38,070 440 — Sovereign debt 20,236 — 20,236 — Total financial instruments sold, but not yet purchased $ 778,863 $ 480,472 $ 298,391 $ — The following table summarizes the changes in fair value associated with Level 3 financial instruments during the three months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 Financial instruments owned Investments Mortgage- Backed Securities – Non-Agency Asset-Backed Securities Equity Securities Auction Securities – Equity Auction Rate Securities – Municipal Other Balance at June 30, 2018 $ 1 $ 355 $ 123 $ 25,303 $ 846 $ 857 Unrealized gains/(losses): Included in changes in net assets (1) — — — 997 3 — Realized gains/(losses) (1) — — (22 ) — — — Purchases — — — — — — Sales — — — — — — Redemptions — — — (9,775 ) (50 ) — Transfers: Into Level 3 — — — — — — Out of Level 3 — — — — — — Net change — — (22 ) (8,778 ) (47 ) — Balance at September 30, 2018 $ 1 $ 355 $ 101 $ 16,525 $ 799 $ 857 (1) Realized and unrealized gains/(losses) related to financial instruments owned and investments are reported in other income in the consolidated statements of operations. The following table summarizes the change in fair value associated with Level 3 financial instruments during the nine months ended September 30, 2018 (in thousands): Nine Months Ended September 30, 2018 Financial instruments owned Investments Mortgage- Backed Securities – Non-Agency Asset-Backed Securities Fixed Income Securities Equity Securities Auction Securities – Equity Auction Rate Securities – Municipal Other Balance at December 31, 2017 $ 1 $ 357 $ 242 $ 253 $ 34,789 $ 846 $ 857 Unrealized gains/(losses): Included in changes in net assets (1) — 3 — (130 ) 1,086 3 — Realized gains/(losses) (1) — — — (22 ) — — — Purchases — — — — — — — Sales — — — — — — — Redemptions — (5 ) (242 ) — (19,350 ) (50 ) — Transfers: Into Level 3 — — — — — — — Out of Level 3 — — — — — — — Net change — (2 ) (242 ) (152 ) (18,264 ) (47 ) — Balance at September 30, 2018 $ 1 $ 355 $ — $ 101 $ 16,525 $ 799 $ 857 (1) Realized and unrealized gains/(losses) related to financial instruments owned and investments are reported in other income in the consolidated statements of operations. The results included in the tables above are only a component of the overall investment strategies of our company. The tables above do not present Level 1 or Level 2 valued assets or liabilities. The changes in unrealized gains/(losses) recorded in earnings for the three and nine months ended September 30, 2018, relating to Level 3 assets still held at September 30, 2018, were immaterial. The following table summarizes quantitative information related to the significant unobservable inputs utilized in our company’s Level 3 recurring fair value measurements as of September 30, 2018. Valuation technique Unobservable input Range Weighted average Investments: Auction rate securities: Equity securities Discounted cash flow Discount rate 0.6% - 6.5% 3.8% Workout period 2-3 years 2.4 years Municipal securities Discounted cash flow Discount rate 0.5% - 9.9% 3.2% Workout period 1-4 years 2.0 years The fair value of certain Level 3 assets was determined using various methodologies, as appropriate, including third-party pricing vendors and broker quotes. These inputs are evaluated for reasonableness through various procedures, including due diligence reviews of third-party pricing vendors, variance analyses, consideration of current market environment, and other analytical procedures. The fair value for our auction rate securities was determined using an income approach based on an internally developed discounted cash flow model. The discounted cash flow model utilizes two significant unobservable inputs: discount rate and workout period. The discount rate was calculated using credit spreads of the underlying collateral or similar securities. The workout period was based on an assessment of publicly available information on efforts to re-establish functioning markets for these securities and our company’s own redemption experience. Significant increases in any of these inputs in isolation would result in a significantly lower fair value. On an ongoing basis, management verifies the fair value by reviewing the appropriateness of the discounted cash flow model and its significant inputs. Transfers Within the Fair Value Hierarchy We assess our financial instruments on a quarterly basis to determine the appropriate classification within the fair value hierarchy. Transfers between fair value classifications occur when there are changes in pricing observability levels. Transfers of financial instruments among the levels are deemed to occur at the beginning of the reporting period. There were no transfers of financial assets from Level 2 to Level 1 during the three months ended September 30, 2018. There were $0.6 million of transfers of financial assets from Level 2 to Level 1 during the nine months ended September 30, 2018. There were $0.1 million and $0.7 million of transfers of financial assets from Level 1 to Level 2 during the three and nine months ended September 30, 2018, respectively, primarily related to corporate fixed income securities for which there were low volumes of recent trade activity observed. There were no transfers into or out of Level 3 during the nine months ended September 30, 2018. Fair Value of Financial Instruments The following reflects the fair value of financial instruments as of September 30, 2018 and December 31, 2017, whether or not recognized in the consolidated statements of financial condition at fair value (in thousands) September 30, 2018 December 31, 2017 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial assets: Cash and cash equivalents $ 694,302 $ 694,302 $ 696,283 $ 696,283 Cash segregated for regulatory purposes 21,585 21,585 90,802 90,802 Securities purchased under agreements to resell 622,361 622,361 512,220 512,220 Financial instruments owned 1,162,732 1,162,732 1,143,684 1,143,684 Available-for-sale securities 3,349,607 3,349,607 3,773,508 3,773,508 Held-to-maturity securities 4,565,453 4,506,385 3,698,098 3,710,478 Loans held for sale 262,063 262,063 226,068 226,068 Bank loans 8,253,989 8,330,974 6,947,759 6,953,328 Investments 79,170 79,170 111,379 111,379 Derivative contracts (1) 11,117 11,117 7,995 7,995 Financial liabilities: Securities sold under agreements to repurchase $ 495,484 $ 495,484 $ 233,704 $ 233,704 Bank deposits 14,502,952 13,711,447 13,411,935 12,702,746 Financial instruments sold, but not yet purchased 911,374 911,374 778,863 778,863 Federal Home Loan Bank advances 1,064,000 1,064,000 745,000 745,000 Borrowings 140,030 140,030 256,000 256,000 Senior notes 1,015,714 1,012,374 1,014,940 1,044,768 Debentures to Stifel Financial Capital Trusts 67,500 68,839 67,500 64,962 (1) The following table presents the estimated fair values of financial instruments not measured at fair value on a recurring basis as of September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 Total Level 1 Level 2 Level 3 Financial assets: Cash $ 675,606 $ 675,606 $ — $ — Cash segregated for regulatory purposes 21,585 21,585 — — Securities purchased under agreements to resell 622,361 586,829 35,532 — Held-to-maturity securities 4,506,385 — 4,345,021 161,364 Loans held for sale 262,063 — 262,063 — Bank loans 8,330,974 — 8,330,974 — Financial liabilities: Securities sold under agreements to repurchase $ 495,484 $ 126,378 $ 369,106 $ — Bank deposits 13,711,447 — 13,711,447 — Federal Home Loan Bank advances 1,064,000 1,064,000 — — Borrowings 140,030 140,030 — — Senior notes 1,012,374 1,012,374 — — Debentures to Stifel Financial Capital Trusts 68,839 — — 68,839 December 31, 2017 Total Level 1 Level 2 Level 3 Financial assets: Cash $ 618,842 $ 618,842 $ — $ — Cash segregated for regulatory purposes 90,802 90,802 — — Securities purchased under agreements to resell 512,220 428,740 83,480 — Held-to-maturity securities 3,710,478 — 3,517,781 192,697 Loans held for sale 226,068 — 226,068 — Bank loans 6,953,328 — 6,953,328 — Financial liabilities: Securities sold under agreements to repurchase $ 233,704 $ 92,278 $ 141,426 $ — Bank deposits 12,702,746 — 12,702,746 — Federal Home Loan Bank advances 745,000 745,000 — — Borrowings 256,000 256,000 — — Senior notes 1,044,768 1,044,768 — — Debentures to Stifel Financial Capital Trusts 64,962 — — 64,962 The following, as supplemented by the discussion above, describes the valuation techniques used in estimating the fair value of our financial instruments as of September 30, 2018 and December 31, 2017. Financial Assets Securities Purchased Under Agreements to Resell Securities purchased under agreements to resell are collateralized financing transactions that are recorded at their contractual amounts plus accrued interest. The carrying values at September 30, 2018 and December 31, 2017 approximate fair value due to their short-term nature. Held-to-Maturity Securities Securities held to maturity are recorded at amortized cost based on our company’s positive intent and ability to hold these securities to maturity. Securities held to maturity include agency mortgage-backed securities, asset-backed securities, consisting of collateralized loan obligation securities and corporate fixed income securities. The estimated fair value, included in the above table, is determined using several factors; however, primary weight is given to discounted cash flow modeling techniques that incorporated an estimated discount rate based upon recent observable debt security issuances with similar characteristics. Loans Held for Sale Loans held for sale consist of fixed-rate and adjustable-rate residential real estate mortgage loans intended for sale. Loans held for sale are stated at lower of cost or market value. Market value is determined based on prevailing market prices for loans with similar characteristics or on sale contract prices. Bank Loans The fair values of mortgage loans and commercial loans were estimated using a discounted cash flow method, a form of the income approach. Discount rates were determined considering rates at which similar portfolios of loans, with similar remaining maturities, would be made and considering liquidity spreads applicable to each loan portfolio based on the secondary market. Financial Liabilities Securities Sold Under Agreements to Repurchase Securities sold under agreements to repurchase are collateralized financing transactions that are recorded at their contractual amounts plus accrued interest. The carrying values at September 30, 2018 and December 31, 2017 approximate fair value due to the short-term nature. Bank Deposits The fair value of interest-bearing deposits, including certificates of deposits, demand deposits, savings, and checking accounts, was calculated by discounting the future cash flows using discount rates based on the replacement cost of funding of similar structures and terms. Borrowings The carrying amount of borrowings approximates fair value due to the relative short-term nature of such borrowings. In addition, Stifel Bancorp’s FHLB advances reflect terms that approximate current market rates for similar borrowings. Senior Notes The fair value of our senior notes is estimated based upon quoted market prices. Debentures to Stifel Financial Capital Trusts The fair value of our trust preferred securities is based on the discounted value of contractual cash flows. We have assumed a discount rate based on the coupon achieved in our 4.250% senior notes due 2024. These fair value disclosures represent our best estimates based on relevant market information and information about the financial instruments. Fair value estimates are based on judgments regarding future expected losses, current economic conditions, risk characteristics of the various instruments, and other factors. These estimates are subjective in nature and involve uncertainties and matters of significant judgment and, therefore, cannot be determined with precision. Changes in the above methodologies and assumptions could significantly affect the estimates.

Financial Instruments Owned And

Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased	9 Months Ended
	Sep. 30, 2018
Investments Debt And Equity Securities [Abstract]
Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased	NOTE 5 – Financial Instruments Owned and Financial Instruments Sold, But Not Yet Purchased The components of financial instruments owned and financial instruments sold, but not yet purchased, at September 30, 2018 and December 31, 2017 are as follows (in thousands) September 30, 2018 December 31, 2017 Financial instruments owned: U.S. government securities $ 36,214 $ 13,466 U.S. government agency securities 167,886 147,223 Mortgage-backed securities: Agency 380,044 302,445 Non-agency 23,747 29,356 Asset-backed securities 29,806 76,752 Corporate securities: Fixed income securities 290,627 325,471 Equity securities 69,205 46,802 Sovereign debt 15,996 32,470 State and municipal securities 149,207 169,699 $ 1,162,732 $ 1,143,684 Financial instruments sold, but not yet purchased: U.S. government securities $ 512,275 $ 442,402 U.S. government agency securities — 10,348 Mortgage-backed securities: Agency 95,312 86,612 Corporate securities: Fixed income securities 213,335 180,755 Equity securities 78,895 38,510 Sovereign debt 11,557 20,236 $ 911,374 $ 778,863 At September 30, 2018 and December 31, 2017, financial instruments owned in the amount of $534.6 million and $810.3 million, respectively, were pledged as collateral for our repurchase agreements and short-term borrowings. Our financial instruments owned are presented on a trade-date basis in the consolidated statements of financial condition. Financial instruments sold, but not yet purchased, represent obligations of our company to deliver the specified security at the contracted price, thereby creating a liability to purchase the security in the market at prevailing prices in future periods. We are obligated to acquire the securities sold short at prevailing market prices in future periods, which may exceed the amount reflected in the consolidated statements of financial condition.

Available-For-Sale And Held-To-

Available-For-Sale And Held-To-Maturity Securities	9 Months Ended
	Sep. 30, 2018
Investments Debt And Equity Securities [Abstract]
Available-For-Sale And Held-To-Maturity Securities	NOTE 6 – Available-for-Sale and Held-to-Maturity Securities The following tables provide a summary of the amortized cost and fair values of the available-for-sale securities and held-to-maturity securities at September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 Amortized Cost Gross Unrealized Gains (1) Gross Unrealized Losses (1) Estimated Fair Value Available-for-sale securities U.S. government agency securities $ 5,226 $ — $ (61 ) $ 5,165 State and municipal securities 73,253 — (4,377 ) 68,876 Mortgage-backed securities: Agency 256,120 29 (5,341 ) 250,808 Commercial 74,698 8 (5,883 ) 68,823 Non-agency 1,281 — (12 ) 1,269 Corporate fixed income securities 1,200,498 2,542 (25,725 ) 1,177,315 Asset-backed securities 1,782,052 3,109 (7,810 ) 1,777,351 $ 3,393,128 $ 5,688 $ (49,209 ) $ 3,349,607 Held-to-maturity securities (2) Mortgage-backed securities: Agency $ 1,244,582 $ — $ (48,907 ) $ 1,195,675 Commercial 55,351 — (343 ) 55,008 Asset-backed securities 3,265,520 4,940 (14,758 ) 3,255,702 $ 4,565,453 $ 4,940 $ (64,008 ) $ 4,506,385 December 31, 2017 Amortized Cost Gross Unrealized Gains (1) Gross Unrealized Losses (1) Estimated Fair Value Available-for-sale securities U.S. government agency securities $ 5,022 $ — $ (39 ) $ 4,983 State and municipal securities 74,691 — (4,132 ) 70,559 Mortgage-backed securities: Agency 308,409 102 (2,981 ) 305,530 Commercial 75,548 28 (3,088 ) 72,488 Non-agency 1,568 — — 1,568 Corporate fixed income securities 1,213,262 3,832 (5,652 ) 1,211,442 Asset-backed securities 2,098,958 12,877 (4,897 ) 2,106,938 $ 3,777,458 $ 16,839 $ (20,789 ) $ 3,773,508 Held-to-maturity securities (2) Mortgage-backed securities: Agency $ 1,334,833 $ 13,621 $ (16,208 ) $ 1,332,246 Commercial 58,971 1,313 — 60,284 Asset-backed securities 2,264,283 15,526 (1,862 ) 2,277,947 Corporate fixed income securities 40,011 27 (37 ) 40,001 $ 3,698,098 $ 30,487 $ (18,107 ) $ 3,710,478 (1) Unrealized gains/(losses) related to available-for-sale securities are reported in accumulated other comprehensive loss. (2) Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements. For the three and nine months ended September 30, 2018, we received proceeds of $55.4 million from the sale of available-for-sale securities, which resulted in a realized loss of $0.4 million. There were no sales of available-for-sale securities during the three months ended September 30, 2017. For the nine months ended September 30, 2017, we received proceeds of $87.3 million from the sale of available-for-sale securities, which resulted in realized gains of $0.4 million. During the three months ended September 30, 2018 and September 30, 2017, unrealized losses, net of deferred taxes, of $3.1 million and unrealized gains, net of deferred taxes of $4.7 million were recorded in accumulated other comprehensive loss in the consolidated statements of financial condition. During the nine months ended September 30, 2018 and September 30, 2017, unrealized losses, net of deferred taxes, of $28.1 million and unrealized gains, net of deferred taxes, of $12.3 million were recorded in accumulated other comprehensive loss in the consolidated statements of financial condition. The table below summarizes the amortized cost and fair values of debt securities by contractual maturity. Expected maturities may differ significantly from contractual maturities, as issuers may have the right to call or prepay obligations with or without call or prepayment penalties. September 30, 2018 Available-for-sale securities Held-to-maturity securities Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Debt securities Within one year $ 37,338 $ 37,275 $ — $ — After one year through three years 380,761 372,133 — — After three years through five years 351,855 345,895 — — After five years through ten years 698,866 689,934 478,024 478,491 After ten years 1,592,209 1,583,470 2,787,496 2,777,211 Mortgage-backed securities After one year through three years 163 163 55,351 55,008 After three years through five years 1,360 1,365 — — After five years through ten years 6,242 6,194 180,433 173,389 After ten years 324,334 313,178 1,064,149 1,022,286 $ 3,393,128 $ 3,349,607 $ 4,565,453 $ 4,506,385 The maturities of our available-for-sale (fair value) and held-to-maturity (amortized cost) securities at September 30, 2018, are as follows ( in thousands Within 1 Year 1-5 Years 5-10 Years After 10 Years Total Available-for-sale: (1) U.S. government agency securities $ 1,657 $ 3,508 $ — $ — $ 5,165 State and municipal securities 395 — 18,272 50,209 68,876 Mortgage-backed securities: Agency — 1,528 6,194 243,086 250,808 Commercial — — — 68,823 68,823 Non-agency — — — 1,269 1,269 Corporate fixed income securities 35,223 714,520 427,572 — 1,177,315 Asset-backed securities — — 244,090 1,533,261 1,777,351 $ 37,275 $ 719,556 $ 696,128 $ 1,896,648 $ 3,349,607 Held-to-maturity: Mortgage-backed securities: Agency $ — $ — $ 180,433 $ 1,064,149 $ 1,244,582 Commercial — 55,351 — — 55,351 Asset-backed securities — — 478,024 2,787,496 3,265,520 $ — $ 55,351 $ 658,457 $ 3,851,645 $ 4,565,453 (1) Due to the immaterial amount of income recognized on tax-exempt securities, yields were not calculated on a tax-equivalent basis. At September 30, 2018 and December 31, 2017, securities of $2.0 billion and $2.2 billion, respectively, were pledged at the Federal Home Loan Bank as collateral for borrowings and letters of credit obtained to secure public deposits. At September 30, 2018 and December 31, 2017, securities of $2.1 billion and $2.0 billion, respectively, were pledged with the Federal Reserve discount window. The following table shows the gross unrealized losses and fair value of the Company’s investment securities with unrealized losses, aggregated by investment category and length of time the individual investment securities have been in continuous unrealized loss positions, at September 30, 2018 (in thousands) Less than 12 months 12 months or more Total Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Available-for-sale securities U.S. government securities $ (61 ) $ 5,040 $ — $ — $ (61 ) $ 5,040 State and municipal securities — — (4,377 ) 68,481 (4,377 ) 68,481 Mortgage-backed securities: Agency (731 ) 40,606 (4,610 ) 188,110 (5,341 ) 228,716 Commercial — — (5,883 ) 67,841 (5,883 ) 67,841 Non-agency (12 ) 1,261 — — (12 ) 1,261 Corporate fixed income securities (14,053 ) 565,671 (11,672 ) 310,351 (25,725 ) 876,022 Asset-backed securities (7,810 ) 517,276 — — (7,810 ) 517,276 $ (22,667 ) $ 1,129,854 $ (26,542 ) $ 634,783 $ (49,209 ) $ 1,764,637 Held-to-maturity securities Mortgage-backed securities: Agency $ (11,804 ) $ 556,381 $ (37,103 ) $ 639,295 $ (48,907 ) $ 1,195,676 Commercial (343 ) 55,008 — — (343 ) 55,008 Asset-backed securities (12,298 ) 1,675,810 (2,460 ) 42,507 (14,758 ) 1,718,317 $ (24,445 ) $ 2,287,199 $ (39,563 ) $ 681,802 $ (64,008 ) $ 2,969,001 At September 30, 2018, the amortized cost of 232 securities classified as available for sale exceeded their fair value by $49.2 million, of which $26.5 million related to investment securities that had been in a loss position for 12 months or longer. The total fair value of these investments at September 30, 2018, was $1.8 billion, which was 52.7% of our available-for-sale portfolio. At September 30, 2018, the carrying value of 152 securities held to maturity exceeded their fair value by $64.0 million, of which $39.6 million related to securities held to maturity that have been in a loss position for 12 months or longer. As discussed in more detail below, we conduct periodic reviews of all securities with unrealized losses to assess whether the impairment is other-than-temporary. Other-Than-Temporary Impairment We evaluate all securities in an unrealized loss position quarterly to assess whether the impairment is other-than-temporary. Our other-than-temporary impairment (“OTTI”) assessment is a subjective process requiring the use of judgments and assumptions. There was no credit-related OTTI recognized during the three and nine months ended September 30, 2018 and 2017. We believe the gross unrealized losses of $113.2 million related to our investment portfolio, as of September 30, 2018, are attributable to issuer-specific credit spreads and changes in market interest rates and asset spreads. We, therefore, do not expect to incur any credit losses related to these securities. In addition, we have no intent to sell these securities with unrealized losses, and it is not more likely than not that we will be required to sell these securities prior to recovery of the amortized cost. Accordingly, we have concluded that the impairment on these securities is not other-than-temporary.

Bank Loans

Bank Loans	9 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
Bank Loans	NOTE 7 – Bank Loans Our loan portfolio consists primarily of the following segments: Real Estate. Real estate loans include commercial real estate, residential real estate non-conforming loans, residential real estate conforming loans and home equity lines of credit. The allowance methodology related to real estate loans considers several factors, including, but not limited to, loan-to-value ratio, FICO score, home price index, delinquency status, credit limits, and utilization rates. Commercial and industrial (C&I). C&I loans primarily include commercial and industrial lending used for general corporate purposes, working capital and liquidity, and “event-driven." “Event-driven” loans support client merger, acquisition or recapitalization activities. C&I lending is structured as revolving lines of credit, letter of credit facilities, term loans and bridge loans. Risk factors considered in determining the allowance for corporate loans include the borrower’s financial strength, seniority of the loan, collateral type, leverage, volatility of collateral value, debt cushion, and covenants. Securities-based loans. Securities-based loans allow clients to borrow money against the value of qualifying securities for any suitable purpose other than purchasing, trading, or carrying securities or refinancing margin debt. The majority of consumer loans are structured as revolving lines of credit and letter of credit facilities and are primarily offered through Stifel’s Pledged Asset ("SPA") program. The allowance methodology for securities-based lending considers the collateral type underlying the loan, including the liquidity and trading volume of the collateral, position concentration and other borrower specific factors such as personal guarantees. Construction and land. Short-term loans used to finance the development of a real estate project. Other. Other loans include consumer, credit card, and indirect lending. The following table presents the balance and associated percentage of each major loan category in our bank loan portfolio at September 30, 2018 and December 31, 2017 (in thousands, except percentages) September 30, 2018 December 31, 2017 Balance Percent Balance Percent Commercial and industrial $ 3,127,435 37.5 % $ 2,437,938 34.8 % Residential real estate 2,792,269 33.5 2,593,576 37.0 Securities-based loans 1,836,450 22.0 1,819,206 25.9 Commercial real estate 328,814 3.9 116,258 1.7 Construction and land 120,969 1.4 7,896 0.1 Home equity lines of credit 29,118 0.3 15,039 0.2 Other 109,571 1.4 24,508 0.3 Gross bank loans 8,344,626 100.0 % 7,014,421 100.0 % Unamortized loan premium/(discount), net (13,419 ) 788 Loans in process (2,755 ) (856 ) Unamortized loan fees, net 6,237 872 Allowance for loan losses (80,700 ) (67,466 ) Bank loans, net $ 8,253,989 $ 6,947,759 At September 30, 2018 and December 31, 2017, Stifel Bancorp had loans outstanding to its executive officers, directors, and their affiliates in the amount of $4.0 million and $4.0 million, respectively, and loans outstanding to other Stifel Financial Corp. executive officers, directors, and their affiliates in the amount of $25.2 million and $8.4 million, respectively. At September 30, 2018 and December 31, 2017, we had loans held for sale of $262.1 million and $226.1 million, respectively. For the three months ended September 30, 2018 and 2017, we recognized gains of $2.6 million and $3.2 million, respectively, from the sale of originated loans, net of fees and costs. For the nine months ended September 30, 2018 and 2017, we recognized gains of $7.8 million and $9.4 million, respectively, from the sale of originated loans, net of fees and costs. The following table details activity in the allowance for loan losses by portfolio segment for the three and nine months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 59,572 $ 5,008 $ — $ — $ 64,580 Residential real estate 9,328 1,165 — — 10,493 Securities-based loans 1,928 (5 ) — — 1,923 Commercial real estate 1,672 90 — — 1,762 Construction and land 303 600 — — 903 Home equity lines of credit 229 — — — 229 Other 13 (3 ) — 1 11 Qualitative 730 69 — — 799 $ 73,775 $ 6,924 $ — $ 1 $ 80,700 Nine Months Ended September 30, 2018 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 54,474 $ 10,118 $ (12 ) $ — $ 64,580 Residential real estate 8,430 2,063 — — 10,493 Securities-based loans 2,088 (165 ) — — 1,923 Commercial real estate 1,520 242 — — 1,762 Construction and land 100 803 — — 903 Home equity lines of credit 162 65 — 2 229 Other 16 (5 ) (2 ) 2 11 Qualitative 676 123 — — 799 $ 67,466 $ 13,244 $ (14 ) $ 4 $ 80,700 The following table presents the recorded balances of loans and amount of allowance allocated based upon impairment method by portfolio segment at September 30, 2018 (in thousands) Allowance for Loan Losses Recorded Investment in Loans Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial and industrial $ 8,677 $ 55,903 $ 64,580 $ 23,630 $ 3,103,805 $ 3,127,435 Residential real estate 24 10,469 10,493 328 2,791,941 2,792,269 Securities-based loans — 1,923 1,923 — 1,836,450 1,836,450 Commercial real estate — 1,762 1,762 — 328,814 328,814 Construction and land — 903 903 — 120,969 120,969 Home equity lines of credit — 229 229 231 28,887 29,118 Other — 11 11 58 109,513 109,571 Qualitative — 799 799 — — — $ 8,701 $ 71,999 $ 80,700 $ 24,247 $ 8,320,379 $ 8,344,626 The following table details activity in the allowance for loan losses by portfolio segment for the three and nine months ended September 30, 2017 (in thousands) Three Months Ended September 30, 2017 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 40,805 $ 6,312 $ — $ 35 $ 47,152 Residential real estate 5,569 1,566 — — 7,135 Securities-based loans 3,600 (288 ) — — 3,312 Commercial real estate 932 95 — — 1,027 Home equity lines of credit 283 (13 ) — 1 271 Construction and land 224 9 — — 233 Other 105 (3 ) — 1 103 Qualitative 2,684 312 — — 2,996 $ 54,202 $ 7,990 $ — $ 37 $ 62,229 Nine Months Ended September 30, 2017 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 35,127 $ 12,239 $ (250 ) $ 36 $ 47,152 Residential real estate 2,660 4,475 — — 7,135 Securities-based loans 3,094 218 — — 3,312 Commercial real estate 1,363 2,367 (2,703 ) — 1,027 Home equity lines of credit 371 (102 ) — 2 271 Construction and land 232 1 — — 233 Other 129 (27 ) — 1 103 Qualitative 2,187 809 — — 2,996 $ 45,163 $ 19,980 $ (2,953 ) $ 39 $ 62,229 The following table presents the recorded balances of loans and amount of allowance allocated based upon impairment method by portfolio segment at December 31, 2017 (in thousands) Allowance for Loan Losses Recorded Investment in Loans Individually Evaluated Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Residential real estate $ 24 $ 8,406 $ 8,430 $ 171 $ 2,593,405 $ 2,593,576 Commercial and industrial 9,059 45,415 54,474 28,856 2,409,082 2,437,938 Securities-based loans — 2,088 2,088 — 1,819,206 1,819,206 Commercial real estate — 1,520 1,520 — 116,258 116,258 Home equity lines of credit 20 142 162 184 14,855 15,039 Construction and land — 100 100 — 7,896 7,896 Other 2 14 16 2 24,506 24,508 Qualitative — 676 676 — — — $ 9,105 $ 58,361 $ 67,466 $ 29,213 $ 6,985,208 $ 7,014,421 In determining the amount of our allowance, we rely on an analysis of our loan portfolio, our experience and our evaluation of general economic conditions. If our assumptions prove to be incorrect, our current allowance may not be sufficient to cover future loan losses and we may experience significant increases to our provision. There are two components of the allowance for loan losses: the inherent allowance component and the specific allowance component. The inherent allowance component of the allowance for loan losses is used to estimate the probable losses inherent in the loan portfolio and includes non-homogeneous loans that have not been identified as impaired and portfolios of smaller balance homogeneous loans. The Company maintains methodologies by loan product for calculating an allowance for loan losses that estimates the inherent losses in the loan portfolio. Qualitative and environmental factors such as economic and business conditions, nature and volume of the portfolio and lending terms, and volume and severity of past due loans may also be considered in the calculations. The allowance for loan losses is maintained at a level reasonable to ensure that it can adequately absorb the estimated probable losses inherent in the portfolio. The specific allowance component of the allowance for loan losses is used to estimate probable losses for non-homogeneous exposures, including loans modified in a Troubled Debt Restructuring (“TDR”), which have been specifically identified for impairment analysis by the Company and determined to be impaired. At September 30, 2018, we had $24.2 million of impaired loans, net of discounts, which included $9.1 million in troubled debt restructurings. The specific allowance on impaired loans at September 30, 2018 was $8.7 million. At December 31, 2017, we had $29.2 million of impaired loans, net of discounts, which included $9.1 million in troubled debt restructurings. The specific allowance on impaired loans at December 31, 2017 was $9.1 million. The gross interest income related to impaired loans, which would have been recorded, had these loans been current in accordance with their original terms, and the interest income recognized on these loans during the three and nine months ended September 30, 2018 and 2017, were insignificant to the consolidated financial statements. The tables below present loans that were individually evaluated for impairment by portfolio segment at September 30, 2018 and December 31, 2017, including the average recorded investment balance for the year to date period presented (in thousands) September 30, 2018 Unpaid Contractual Principal Balance Recorded Investment with No Allowance Recorded Investment with Allowance Total Recorded Investment Related Allowance Average Recorded Investment Commercial and industrial $ 23,630 $ 196 $ 23,434 $ 23,630 $ 8,677 $ 23,783 Residential real estate 353 80 248 328 24 355 Home equity lines of credit 231 184 47 231 — 236 Other 731 26 32 58 — 60 Total $ 24,945 $ 486 $ 23,761 $ 24,247 $ 8,701 $ 24,434 December 31, 2017 Unpaid Contractual Principal Balance Recorded Investment with No Allowance Recorded Investment with Allowance Total Recorded Investment Related Allowance Average Recorded Investment Commercial and industrial $ 28,856 $ 5,211 $ 23,645 $ 28,856 $ 9,059 $ 30,277 Home equity lines of credit 184 — 184 184 20 300 Residential real estate 171 — 171 171 24 174 Other 677 — 2 2 2 5 Total $ 29,888 $ 5,211 $ 24,002 $ 29,213 $ 9,105 $ 30,756 The following table presents the aging of the recorded investment in past due loans at September 30, 2018 and December 31, 2017 by portfolio segment (in thousands) As of September 30, 2018 30 – 89 Days Past Due 90 or More Days Past Due Total Due Current Balance Total Commercial and industrial $ — $ 14,656 $ 14,656 $ 3,112,779 $ 3,127,435 Residential real estate 3,745 184 3,929 2,788,340 2,792,269 Securities-based loans — — — 1,836,450 1,836,450 Commercial real estate — — — 328,814 328,814 Construction and land — — — 120,969 120,969 Home equity lines of credit 47 — 47 29,071 29,118 Other — 67 67 109,504 109,571 Total $ 3,792 $ 14,907 $ 18,699 $ 8,325,927 $ 8,344,626 As of September 30, 2018* Non-Accrual Restructured Total Commercial and industrial $ 14,694 $ 8,936 $ 23,630 Residential real estate 159 169 328 Home equity lines of credit 231 — 231 Other 58 — 58 Total $ 15,142 $ 9,105 $ 24,247 * There were no loans past due 90 days and still accruing interest at September 30, 2018. As of December 31, 2017 30 – 89 Days Past Due 90 or More Days Past Due Total Past Due Current Balance Total Residential real estate $ 7,892 $ — $ 7,892 $ 2,585,684 $ 2,593,576 Commercial and industrial 11,883 — 11,883 2,426,055 2,437,938 Securities-based loans — — — 1,819,206 1,819,206 Commercial real estate — — — 116,258 116,258 Home equity lines of credit 184 — 184 14,855 15,039 Construction and land — — — 7,896 7,896 Other 2 — 2 24,506 24,508 Total $ 19,961 $ — $ 19,961 $ 6,994,460 $ 7,014,421 As of December 31, 2017* Non-Accrual Restructured Total Commercial and industrial $ 19,904 $ 8,952 $ 28,856 Home equity lines of credit 184 — 184 Residential real estate — 171 171 Other 2 — 2 Total $ 20,090 $ 9,123 $ 29,213 * There were no loans past due 90 days and still accruing interest at December 31, 2017. Credit quality indicators Loans meet the definition of Pass when they are performing and do not demonstrate adverse characteristics that are likely to result in a credit loss. A loan is determined to be impaired when principal or interest becomes 90 days past due or when collection becomes uncertain. At the time a loan is determined to be impaired, the accrual of interest and amortization of deferred loan origination fees is discontinued (“non-accrual status”), and any accrued and unpaid interest income is reversed. We closely monitor economic conditions and loan performance trends to manage and evaluate our exposure to credit risk. Trends in delinquency ratios are an indicator, among other considerations, of credit risk within our loan portfolio. The level of nonperforming assets represents another indicator of the potential for future credit losses. Accordingly, key metrics we track and use in evaluating the credit quality of our loan portfolio include delinquency and nonperforming asset rates, as well as charge-off rates and our internal risk ratings of the loan portfolio. In general, we are a secured lender. At September 30, 2018 and December 31, 2017, 98.6% and 97.2% of our loan portfolio was collateralized, respectively. Collateral is required in accordance with the normal credit evaluation process based upon the creditworthiness of the customer and the credit risk associated with the particular transaction. The Company uses the following definitions for risk ratings: Pass. A credit exposure rated pass has a continued expectation of timely repayment, all obligations of the borrower are current, and the obligor complies with material terms and conditions of the lending agreement. Special Mention. Extensions of credit that have potential weakness that deserve management’s close attention, and if left uncorrected may, at some future date, result in the deterioration of the repayment prospects or collateral position. Substandard. Obligor has a well-defined weakness that jeopardizes the repayment of the debt and has a high probability of payment default with the distinct possibility that the Company will sustain some loss if noted deficiencies are not corrected. Doubtful. Inherent weakness in the exposure makes the collection or repayment in full, based on existing facts, conditions and circumstances, highly improbable, and the amount of loss is uncertain. Doubtful loans are considered impaired. Substandard loans are regularly reviewed for impairment. When a loan is impaired the impairment is measured based on the present value of expected future cash flows discounted at the loan’s effective interest rate, or as a practical expedient, the observable market price of the loan or the fair value of the collateral if the loan is collateral dependent. Based on the most recent analysis performed, the risk category of our loan portfolio was as follows: (in thousands) As of September 30, 2018 Pass Special Substandard Doubtful Total Commercial and industrial $ 3,069,237 $ 34,488 $ 23,710 $ — $ 3,127,435 Residential real estate 2,791,627 394 248 — 2,792,269 Securities-based loans 1,836,450 — — — 1,836,450 Commercial real estate 328,814 — — — 328,814 Construction and land 120,969 — — — 120,969 Home equity lines of credit 28,887 — 231 — 29,118 Other 109,513 — 47 11 109,571 Total $ 8,285,497 $ 34,882 $ 24,236 $ 11 $ 8,344,626 As of December 31, 2017 Pass Special Substandard Doubtful Total Residential real estate $ 2,593,096 $ 309 $ 171 $ — $ 2,593,576 Commercial and industrial 2,385,152 22,443 30,343 — 2,437,938 Securities-based loans 1,819,206 — — — 1,819,206 Commercial real estate 116,258 — — — 116,258 Home equity lines of credit 14,855 — 184 — 15,039 Construction and land 7,896 — — — 7,896 Other 24,506 — 2 — 24,508 Total $ 6,960,969 $ 22,752 $ 30,700 $ — $ 7,014,421

Goodwill And Intangible Assets

Goodwill And Intangible Assets	9 Months Ended
	Sep. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Goodwill And Intangible Assets	NOTE 8 – Goodwill and Intangible Assets The carrying amount of goodwill and intangible assets attributable to each of our reporting segments is presented in the following table (in thousands) December 31, 2017 Adjustments Write-off September 30, 2018 Goodwill Global Wealth Management $ 276,477 $ 54,969 $ — $ 331,446 Institutional Group 692,357 1,911 — 694,268 $ 968,834 $ 56,880 $ — $ 1,025,714 December 31, 2017 Net Additions Amortization September 30, 2018 Intangible assets Global Wealth Management $ 44,525 $ 17,180 $ (3,662 ) $ 58,043 Institutional Group 65,102 857 (5,079 ) 60,880 $ 109,627 $ 18,037 $ (8,741 ) $ 118,923 On March 19, 2018, the Company completed the acquisition of Ziegler. The acquisition was accounted for under the acquisition method of accounting in accordance with ASC 805, “Business Combinations.” Accordingly, goodwill was measured as the excess of the acquisition-date fair value of the consideration transferred over the amount of acquisition-date identifiable assets acquired net of assumed liabilities. We recorded $19.0 million of goodwill in the consolidated statement of financial condition, which has been allocated to our company’s Global Wealth Management and Institutional Group segments. Identifiable intangible assets purchased by our company consisted of customer relationships and non-compete agreements with an acquisition-date fair value of $9.5 million. See Note 1 in the notes to our consolidated financial statements for additional information regarding the acquisition of Ziegler. The goodwill represents the value expected from the synergies created through the operational enhancement benefits that will result from the integration of the Ziegler business and of the hired financial advisors and the conversion of the customer accounts to our platform. Goodwill is expected to be deductible for federal income tax purposes. On August 31, 2018, the Company completed the acquisition of Business Bancshares, Inc. (“BBI”). The acquisition was accounted for under the acquisition method of accounting in accordance with ASC 805, “Business Combinations.” Accordingly, goodwill was measured as the excess of the acquisition-date fair value of the consideration transferred over the amount of acquisition-date identifiable assets acquired net of assumed liabilities. We recorded $46.4 million of goodwill and intangibles in the consolidated statement of financial condition, which has been allocated to our company’s Global Wealth Management segment. The allocation of the purchase price of BBI is preliminary and will be finalized upon completion of the analysis of the fair values of the net assets of BBI as of the acquisition date and the identified intangible assets. The final goodwill recorded on the consolidated statement of financial condition may differ from that reflected herein as a result of future measurement period adjustments and the recording of identified intangible assets. See Note 1 in the notes to our consolidated financial statements for additional information regarding the acquisition of BBI. The goodwill represents the value expected from the synergies created through the operational enhancement benefits that will result from the integration of the BBI business and its customer base. Amortizable intangible assets consist of acquired customer relationships, trade name, investment banking backlog, and non-compete agreements that are amortized over their contractual or determined useful lives. Intangible assets subject to amortization as of September 30, 2018 and December 31, 2017 were as follows (in thousands) September 30, 2018 December 31, 2017 Gross Carrying Value Accumulated Amortization Gross Carrying Value Accumulated Amortization Customer relationships $ 156,240 $ 62,822 $ 146,986 $ 55,809 Trade name 24,713 11,373 24,713 10,228 Non-compete agreements 2,603 1,388 2,598 1,202 Investment banking backlog 1,431 1,214 1,419 968 Estimated BBI intangibles (1) 8,615 — — — $ 193,602 $ 76,797 $ 175,716 $ 68,207 (1) Amortization expense related to intangible assets was $3.0 million and $2.9 million for the three months ended September 30, 2018 and 2017, respectively. Amortization expense related to intangible assets was $8.7 million and $9.1 million for the nine months ended September 30, 2018 and 2017, respectively. Amortization expense is included in other operating expenses in the consolidated statements of operations. The weighted-average remaining lives of the following intangible assets at September 30, 2018, are: customer relationships, 10.7 years; trade name, 9.7 years; non-compete agreements, 8.8 years; and BBI intangibles, 5.0 years. As of September 30, 2018, we expect amortization expense in future periods to be as follows (in thousands) Fiscal year Remainder of 2018 $ 3,382 2019 12,974 2020 12,757 2021 12,258 2022 11,798 Thereafter 63,636 $ 116,805

Borrowings and Federal Home Loa

Borrowings and Federal Home Loan Bank Advances	9 Months Ended
	Sep. 30, 2018
Short Term Debt Other Disclosures [Abstract]
Borrowings and Federal Home Loan Bank Advances	NOTE 9 – Borrowings and Federal Home Loan Bank Advances Our short-term financing is generally obtained through short-term bank line financing on an uncommitted, secured basis, securities lending arrangements, advances from the Federal Home Loan Bank, term loans, and committed bank line financing on an unsecured basis. We borrow from various banks on a demand basis with company-owned and customer securities pledged as collateral. The value of customer-owned securities used as collateral is not reflected in the consolidated statements of financial condition. Our uncommitted secured lines of credit at September 30, 2018, totaled $1.0 billion with six banks and are dependent on having appropriate collateral, as determined by the bank agreements, to secure an advance under the line. The availability of our uncommitted lines is subject to approval by the individual banks each time an advance is requested and may be denied. Our peak daily borrowing on our uncommitted secured lines was $391.0 million during the nine months ended September 30, 2018. There are no compensating balance requirements under these arrangements. Any borrowings on secured lines of credit are generally utilized to finance certain fixed income securities. At September 30, 2018, we had no outstanding balances on our uncommitted secured lines of credit. The Federal Home Loan advances of $1.1 billion as of September 30, 2018 are floating-rate advances. The weighted average interest rates on these advances during the three and nine months ended September 30, 2018 was 1.65% and 1.52%, respectively. The advances are secured by Stifel Bancorp’s residential mortgage loan portfolio and investment portfolio. The interest rates reset on a daily basis. Stifel Bancorp has the option to prepay these advances without penalty on the interest reset date. Our committed bank line financing at September 30, 2018, consisted of a $200.0 million revolving credit facility. The credit facility expires in March 2020. The applicable interest rate under the revolving credit facility is calculated as a per annum rate equal to the London Interbank Offered Rate (“LIBOR”) plus 1.75%, as defined in the revolving credit facility. At September 30, 2018, we had no advances on our revolving credit facility and were in compliance with all covenants. In June 2018, Stifel, our broker-dealer subsidiary, entered into a 364-day Credit Agreement (“Stifel Credit Facility”) with a maturity date of June 2019 in which the lenders are a number of financial institutions. This committed unsecured borrowing facility provides for maximum borrowings of up to $250.0 million at variable rates of interest. At September 30, 2018, we had no advances on the Stifel Credit Facility and were in compliance with all covenants. As of September 30, 2018, a subsidiary of Stifel Bancorp was a party to two Notes. The Notes mature in 2043. The Notes bear interest contractually at fixed rates as per the Note Purchase Agreement. The outstanding balance on the Notes at September 30, 2018 was $134.8 million and is included in borrowings in the consolidated statements of financial condition.

Senior Notes

Senior Notes	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Senior Notes	NOTE 10 – Senior Notes The following table summarizes our senior notes as of September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 December 31, 2017 4.250% senior notes, due 2024 (1) $ 500,000 $ 500,000 3.50% senior notes, due 2020 (2) 300,000 300,000 5.20% senior notes, due 2047 (3) 225,000 225,000 1,025,000 1,025,000 Debt issuance costs, net (9,286 ) (10,060 ) $ 1,015,714 $ 1,014,940 (1) In July 2014, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 4.250% senior notes due July 2024. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption. In July 2016, we issued an additional $200.0 million in aggregate principal amount of 4.25% senior notes due 2024. (2) In December 2015, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 3.50% senior notes due December 2020. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption. (3) Our senior notes mature as follows, based upon contractual terms (in thousands) 2018 $ — 2019 — 2020 300,000 2021 — 2022 — Thereafter 725,000 $ 1,025,000

Bank Deposits

Bank Deposits	9 Months Ended
	Sep. 30, 2018
Deposits Liabilities Balance Sheet Reported Amounts [Abstract]
Bank Deposits	NOTE 11 – Bank Deposits Deposits consist of money market and savings accounts, certificates of deposit, and demand deposits. Deposits at September 30, 2018 and December 31, 2017 were as follows (in thousands) September 30, 2018 December 31, 2017 Money market and savings accounts $ 11,950,269 $ 13,219,675 Certificates of deposit 1,970,318 1,575 Demand deposits (interest-bearing) 465,366 184,829 Demand deposits (non-interest-bearing) 116,999 5,856 $ 14,502,952 $ 13,411,935 The weighted-average interest rate on deposits was 0.49% and 0.10% at September 30, 2018 and December 31, 2017, respectively. Scheduled maturities of certificates of deposit at September 30, 2018 and December 31, 2017 were as follows (in thousands): September 30, 2018 December 31, 2017 Certificates of deposit, less than $100: Within one year $ 5,617 $ 438 One to three years 544 148 Three to five years 127 — $ 6,288 $ 586 Certificates of deposit, $100 and greater: Within one year $ 1,740,855 $ 651 One to three years 193,185 338 Three to five years 29,990 — 1,964,030 989 $ 1,970,318 $ 1,575 At September 30, 2018 and December 31, 2017, the amount of deposits includes related party deposits, primarily interest-bearing and time deposits of executive officers, directors, and their affiliates of $3.8 million and $0.2 million, respectively. Brokerage customers’ deposits were $13.6 billion and $13.4 billion, respectively.

Derivative Instruments And Hedg

Derivative Instruments And Hedging Activities	9 Months Ended
	Sep. 30, 2018
General Discussion Of Derivative Instruments And Hedging Activities [Abstract]
Derivative Instruments And Hedging Activities	NOTE 12 – Derivative Instruments and Hedging Activities We use interest rate swaps as part of our interest rate risk management strategy. Interest rate swaps generally involve the exchange of fixed and variable rate interest payments between two parties, based on a common notional principal amount and maturity date with no exchange of underlying principal amounts. Interest rate swaps designated as cash flow hedges involve the receipt of variable amounts from a counterparty in exchange for our company making fixed payments. Our policy is not to offset fair value amounts recognized for derivative instruments and fair value amounts recognized for the right to reclaim cash collateral or the obligation to return cash collateral arising from derivative instruments recognized at fair value executed with the same counterparty under master netting arrangements. The following table provides the notional values and fair values of our derivative instruments as of September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 Notional Balance Location Fair Value Asset Derivatives Cash flow interest rate contracts $ 540,000 Other assets $ 11,117 December 31, 2017 Notional Value Balance Location Fair Value Asset Derivatives Cash flow interest rate contracts $ 540,000 Other assets $ 7,995 Cash Flow Hedges We have entered into interest rate swap agreements that effectively modify our exposure to interest rate risk by converting floating rate debt to a fixed rate debt. The swaps have an average remaining life of 1.3 years. Any unrealized gains or losses related to cash flow hedging instruments are reclassified from accumulated other comprehensive loss into earnings in the same period the hedged forecasted transaction affects earnings and are recorded in interest expense on the accompanying consolidated statements of operations. The ineffective portion of the cash flow hedging instruments is recorded in other income or other operating expense. Amounts reported in accumulated other comprehensive loss related to derivatives will be reclassified to interest expense as interest payments are made on our variable rate deposits. During the next twelve months, we estimate that $4.9 million will be reclassified as interest income. The following table shows the effect of our company’s derivative instruments in the consolidated statements of operations for the three and nine months ended September 30, 2018 and 2017 (in thousands) Three Months Ended September 30, 2018 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Gain/(Loss) Recognized Due to Ineffectiveness Cash flow interest rate contracts $ (603 ) Interest expense $ 1,504 Interest expense $ — Three Months Ended September 30, 2017 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Gain/(Loss) Recognized Due to Ineffectiveness Cash flow interest rate contracts $ 928 Interest $ 724 Interest expense $ — Nine Months Ended September 30, 2018 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Loss Recognized Due to Ineffectiveness Cash flow interest rate contracts $ (5,823 ) Interest $ 3,262 Interest expense $ — Nine Months Ended September 30, 2017 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Loss Recognized Due to Ineffectiveness Cash flow interest rate contracts $ 3,504 Interest expense $ (810 ) Interest expense $ — We maintain a risk management strategy that incorporates the use of derivative instruments to minimize significant unplanned fluctuations in earnings caused by interest rate volatility. Our goal is to manage sensitivity to changes in rates by hedging the maturity characteristics of variable rate affiliated deposits, thereby limiting the impact on earnings. By using derivative instruments, we are exposed to credit and market risk on those derivative positions. We manage the market risk associated with interest rate contracts by establishing and monitoring limits as to the types and degree of risk that may be undertaken. Credit risk is equal to the extent of the fair value gain in a derivative if the counterparty fails to perform. When the fair value of a derivative contract is positive, this generally indicates that the counterparty owes our company and, therefore, creates a repayment risk for our company. When the fair value of a derivative contract is negative, we owe the counterparty and, therefore, have no repayment risk. See Note 4 in the notes to our consolidated financial statements for further discussion on how we determine the fair value of our financial instruments. We minimize the credit (or repayment) risk in derivative instruments by entering into transactions with high-quality counterparties that are reviewed periodically by senior management. Credit Risk-Related Contingency Features We have agreements with our derivative counterparties containing provisions where if we default on any of our indebtedness, including default where repayment of the indebtedness has not been accelerated by the lender, then we could also be declared in default on our derivative obligations. We have agreements with certain of our derivative counterparties that contain provisions where if our shareholders’ equity declines below a specified threshold or if we fail to maintain a specified minimum shareholders’ equity, then we could be declared in default on our derivative obligations. Certain of our agreements with our derivative counterparties contain provisions where if a specified event or condition occurs that materially changes our creditworthiness in an adverse manner, we may be required to fully collateralize our obligations under the derivative instrument. Regulatory Capital-Related Contingency Features Certain of our derivative instruments contain provisions that require us to maintain our capital adequacy requirements. If we were to lose our status as “adequately capitalized,” we would be in violation of those provisions, and the counterparties of the derivative instruments could request immediate payment or demand immediate and ongoing full overnight collateralization on derivative instruments in net liability positions. Counterparty Risk In the event of counterparty default, our economic loss may be higher than the uncollateralized exposure of our derivatives if we were not able to replace the defaulted derivatives in a timely fashion. We monitor the risk that our uncollateralized exposure to each of our counterparties for interest rate swaps will increase under certain adverse market conditions by performing periodic market stress tests. These tests evaluate the potential additional uncollateralized exposure we would have to each of these derivative counterparties assuming changes in the level of market rates over a brief time period.

Disclosures About Offsetting As

Disclosures About Offsetting Assets And Liabilities	9 Months Ended
	Sep. 30, 2018
Offsetting [Abstract]
Disclosures About Offsetting Assets And Liabilities	NOTE 13 – Disclosures About Offsetting Assets and Liabilities The following table provides information about financial assets and derivative assets that are subject to offset as of September 30, 2018 and December 31, 2017 (in thousands) Gross amounts not offset in the Statement of Financial Condition Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Condition Net Amounts Presented in the of Financial Condition Amounts available for offset Available collateral Net Amount As of September 30, 2018: Securities borrowing (1) $ 170,165 $ — $ 170,165 $ (47,974 ) $ (110,088 ) $ 12,103 Reverse repurchase agreements (2) 622,361 — 622,361 (261,773 ) (356,842 ) 3,746 Cash flow interest rate contracts 11,117 — 11,117 — — 11,117 $ 803,643 $ — $ 803,643 $ (309,747 ) $ (466,930 ) $ 26,966 As of December 31, 2017: Securities borrowing (1) $ 132,776 $ — $ 132,776 $ (78,474 ) $ (37,248 ) $ 17,054 Reverse repurchase agreements (2) 512,220 — 512,220 (233,624 ) (266,008 ) 12,588 Cash flow interest rate contracts 7,995 — 7,995 — — 7,995 $ 652,991 $ — $ 652,991 $ (312,098 ) $ (303,256 ) $ 37,637 (1) Securities borrowing transactions are included in receivables from brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on receivables from brokers, dealers, and clearing organizations. (2) Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively. The following table provides information about financial liabilities and derivative liabilities that are subject to offset as of September 30, 2018 and December 31, 2017 (in thousands) Gross amounts not offset in the Statement of Financial Condition Gross Amounts of Recognized Liabilities Gross Amounts Offset in the of Financial Condition Net Amounts Presented in the Statement of Financial Condition Amounts available for offset Collateral Pledged Net Amount As of September 30, 2018: Securities lending (3) $ (691,150 ) $ — $ (691,150 ) $ 47,974 $ 616,157 $ (27,019 ) Repurchase agreements (4) (495,484 ) — (495,484 ) 261,773 233,711 — $ (1,186,634 ) $ — $ (1,186,634 ) $ 309,747 $ 849,868 $ (27,019 ) As of December 31, 2017: Securities lending (3) $ (219,782 ) $ — $ (219,782 ) $ 78,474 $ 133,772 $ (7,536 ) Repurchase agreements (4) (233,704 ) — (233,704 ) 233,624 80 — $ (453,486 ) $ — $ (453,486 ) $ 312,098 $ 133,852 $ (7,536 ) (3) Securities lending transactions are included in payables to brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on payables to brokers, dealers, and clearing organizations. (4) Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Commitments, Guarantees, And Co

Commitments, Guarantees, And Contingencies	9 Months Ended
	Sep. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments, Guarantees, And Contingencies	NOTE 14 – Commitments, Guarantees, and Contingencies Broker-Dealer Commitments and Guarantees In the normal course of business, we enter into underwriting commitments. Settlement of transactions relating to such underwriting commitments, which were open at September 30, 2018, had no material effect on the consolidated financial statements. We also provide guarantees to securities clearinghouses and exchanges under their standard membership agreement, which requires members to guarantee the performance of other members. Under the agreement, if another member becomes unable to satisfy its obligations to the clearinghouse, other members would be required to meet shortfalls. Our liability under these agreements is not quantifiable and may exceed the cash and securities we have posted as collateral. However, the potential requirement for us to make payments under these arrangements is considered remote. Accordingly, no liability has been recognized for these arrangements. Other Commitments In the ordinary course of business, Stifel Bancorp has commitments to extend credit in the form of commitments to originate loans, standby letters of credit, and lines of credit. See Note 20 in the notes to consolidated financial statements for further details. Concentration of Credit Risk We provide investment, capital-raising, and related services to a diverse group of domestic customers, including governments, corporations, and institutional and individual investors. Our exposure to credit risk associated with the non-performance of customers in fulfilling their contractual obligations pursuant to securities transactions can be directly impacted by volatile securities markets, credit markets, and regulatory changes. This exposure is measured on an individual customer basis and on a group basis for customers that share similar attributes. To reduce the potential for risk concentrations, counterparty credit limits have been implemented for certain products and are continually monitored in light of changing customer and market conditions. As of September 30, 2018 and December 31, 2017, we did not have significant concentrations of credit risk with any one customer or counterparty, or any group of customers or counterparties.

Legal Proceedings

Legal Proceedings	9 Months Ended
	Sep. 30, 2018
Loss Contingency Information About Litigation Matters [Abstract]
Legal Proceedings	NOTE 15 – Legal Proceedings Our company and its subsidiaries are named in and subject to various proceedings and claims arising primarily from our securities business activities, including lawsuits, arbitration claims, class actions, and regulatory matters. Some of these claims seek substantial compensatory, punitive, or indeterminate damages. Our company and its subsidiaries are also involved in other reviews, investigations, and proceedings by governmental and self-regulatory organizations regarding our business, which may result in adverse judgments, settlements, fines, penalties, injunctions, and other relief. We are contesting allegations in these claims, and we believe that there are meritorious defenses in each of these lawsuits, arbitrations, and regulatory investigations. In view of the number and diversity of claims against our company, the number of jurisdictions in which litigation is pending, and the inherent difficulty of predicting the outcome of litigation and other claims, we cannot state with certainty what the eventual outcome of pending litigation or other claims will be. We have established reserves for potential losses that are probable and reasonably estimable that may result from pending and potential legal actions, investigations, and regulatory proceedings. In many cases, however, it is inherently difficult to determine whether any loss is probable or reasonably possible or to estimate the amount or range of any potential loss, particularly where proceedings may be in relatively early stages or where plaintiffs are seeking substantial or indeterminate damages. Matters frequently need to be more developed before a loss or range of loss can reasonably be estimated. In our opinion, based on currently available information, review with outside legal counsel, and consideration of amounts provided for in our consolidated financial statements with respect to these matters, the ultimate resolution of these matters will not have a material adverse impact on our financial position and results of operations. However, resolution of one or more of these matters may have a material effect on the results of operations in any future period, depending upon the ultimate resolution of those matters and depending upon the level of income for such period. For matters where a reserve has not been established and for which we believe a loss is reasonably possible, as well as for matters where a reserve has been recorded but for which an exposure to loss in excess of the amount accrued is reasonably possible, based on currently available information, we believe that such losses will not have a material effect on our consolidated financial statements.

Regulatory Capital Requirements

Regulatory Capital Requirements	9 Months Ended
	Sep. 30, 2018
Regulatory Capital Requirements [Abstract]
Regulatory Capital Requirements	NOTE 16 – Regulatory Capital Requirements We operate in a highly regulated environment and are subject to capital requirements, which may limit distributions to our company from its subsidiaries. Distributions from our broker-dealer subsidiaries are subject to net capital rules. A broker-dealer that fails to comply with the SEC’s Uniform Net Capital Rule (Rule 15c3-1) may be subject to disciplinary actions by the SEC and self-regulatory organizations, such as FINRA, including censures, fines, suspension, or expulsion. Stifel has chosen to calculate its net capital under the alternative method, which prescribes that their net capital shall not be less than the greater of $1.0 million or two percent of aggregate debit balances (primarily receivables from customers) computed in accordance with the SEC’s Customer Protection Rule (Rule 15c3-3). Our other broker-dealer subsidiaries calculate their net capital under the aggregate indebtedness method, whereby their aggregate indebtedness may not be greater than fifteen times their net capital (as defined). At September 30, 2018, Stifel had net capital of $355.9 million, which was 20.0% of aggregate debit items and $320.4 million in excess of its minimum required net capital. At September 30, 2018, all of our other broker-dealer subsidiaries’ net capital exceeded the minimum net capital required under the SEC rule. Our international subsidiary is subject to the regulatory supervision and requirements of the Financial Conduct Authority (“FCA”) in the United Kingdom. At September 30, 2018, our international subsidiary’s capital and reserves were in excess of the financial resources requirement under the rules of the FCA. Our company, as a bank holding company, Stifel Bank & Trust, and Stifel Bank (“bank subsidiaries”) are subject to various regulatory capital requirements administered by the Federal and state banking agencies. Failure to meet minimum capital requirements can initiate certain mandatory and possibly additional discretionary actions by regulators that, if undertaken, could have a direct material effect on our company’s and its bank subsidiaries’ financial results. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, our company and its bank subsidiaries must meet specific capital guidelines that involve quantitative measures of our assets, liabilities, and certain off-balance sheet items as calculated under regulatory accounting practices. Our company’s and its bank subsidiaries’ capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings, and other factors. Our company and its bank subsidiaries are subject to Basel III. Under the Basel III rules, the quantity and quality of regulatory capital increased, a capital conservation buffer was established, selected changes were made to the calculation of risk-weighted assets, and a new ratio, common equity Tier 1 was introduced, all of which are applicable to both our company and its bank subsidiaries. Various aspects of Basel III will be subject to multi-year transition periods through December 31, 2018. Our company and its bank subsidiaries are required to maintain minimum amounts and ratios of Total and Tier 1 capital (as defined in the regulations) to risk-weighted assets (as defined), Tier 1 capital to average assets (as defined), and under rules defined in Basel III, Common equity Tier 1 capital to risk-weighted assets. Our company and its bank subsidiaries each calculate these ratios in order to assess compliance with both regulatory requirements and their internal capital policies. At current capital levels, our company and its bank subsidiaries are each categorized as “well capitalized” under the regulatory framework for prompt corrective action. To be categorized as “well capitalized,” our company and its bank subsidiaries must maintain total risk-based, Tier 1 risk-based, and Tier 1 leverage ratios as set forth in the tables below (in thousands, except ratios). Stifel Financial Corp. – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 1,931,840 16.7 % $ 521,580 4.5 % $ 753,393 6.5 % Tier 1 capital 2,081,840 18.0 % 695,439 6.0 % 927,252 8.0 % Total capital 2,232,951 19.3 % 927,252 8.0 % 1,159,066 10.0 % Tier 1 leverage 2,081,840 9.6 % 864,465 4.0 % 1,080,581 5.0 % Stifel Bank & Trust – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 1,142,936 14.2 % $ 361,454 4.5 % $ 522,100 6.5 % Tier 1 capital 1,142,936 14.2 % 481,939 6.0 % 642,585 8.0 % Total capital 1,223,636 15.2 % 642,585 8.0 % 803,231 10.0 % Tier 1 leverage 1,142,936 7.0 % 651,837 4.0 % 814,797 5.0 % Stifel Bank – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 75,385 13.8 % $ 24,666 4.5 % $ 35,629 6.5 % Tier 1 capital 75,385 13.8 % 32,888 6.0 % 43,851 8.0 % Total capital 82,246 15.0 % 43,851 8.0 % 54,814 10.0 % Tier 1 leverage 75,385 12.5 % 24,137 4.0 % 30,171 5.0 %

Revenues from Contracts with Cu

Revenues from Contracts with Customers	9 Months Ended
	Sep. 30, 2018
Revenue From Contract With Customer [Abstract]
Revenues from Contracts with Customers	NOTE 17 – Revenues from Contracts with Customers The following table presents the Company’s total revenues separated between revenues from contracts with customers and other sources of revenues for the three and nine months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 Nine Months Ended September 30, 2018 Revenues from contracts with customers: Commissions $ 158,016 $ 490,693 Investment banking 169,012 506,437 Asset management and service fees 200,743 596,112 Other 4,394 11,908 Total revenue from contracts with customers 532,165 1,605,150 Other sources of revenue: Interest 169,760 461,915 Principal transactions 83,152 269,918 Other 1,733 6,649 Total revenues $ 786,810 $ 2,343,632 Revenue from contracts with customers is recognized when, or as, we satisfy our performance obligations by transferring the promised goods or services to the customers. A good or service is transferred to a customer when, or as, the customer obtains control of that good or service. A performance obligation may be satisfied over time or at a point in time. Revenue from a performance obligation satisfied over time is recognized by measuring our progress in satisfying the performance obligation in a manner that depicts the transfer of the goods or services to the customer. Revenue from a performance obligation satisfied at a point in time is recognized at the point in time that we determine the customer obtains control over the promised good or service. The amount of revenue recognized reflects the consideration we expect to be entitled to in exchange for those promised goods or services (i.e., the “transaction price”). In determining the transaction price, we consider multiple factors, including the effects of variable consideration. Variable consideration is included in the transaction price only to the extent it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainties with respect to the amount are resolved. In determining when to include variable consideration in the transaction price, we consider the range of possible outcomes, the predictive value of our past experiences, the time period of when uncertainties expect to be resolved and the amount of consideration that is susceptible to factors outside of our influence, such as market volatility or the judgment and actions of third parties. The following provides detailed information on the recognition of our revenues from contracts with customers: Commissions. We earn commission revenue by executing, settling, and clearing transactions for clients primarily in OTC and listed equity securities, insurance products, and options. Trade execution and clearing and custody services, when provided together, represent a single performance obligation as the services are not separately identifiable in the context of the contract. Commission revenues associated with combined trade execution and clearing and custody services, as well as trade execution services on a standalone basis, are recognized at a point in time on trade-date. Commission revenues are generally paid on settlement date and we record a receivable between trade-date and payment on settlement date. Investment Banking. We provide our clients with a full range of capital markets and financial advisory services. Capital markets services include underwriting and placement agent services in both the equity and debt capital markets, including private equity placements, initial public offerings, follow-on offerings, underwriting and distributing public and private debt. Capital raising revenues are recognized at a point in time on trade-date, as the client obtains the control and benefit of the capital markets offering at that point. Costs associated with capital raising transactions are deferred until the related revenue is recognized or the engagement is otherwise concluded, and are recorded on a gross basis within other operating expenses in the consolidated statements of operations as we are acting as a principal in the arrangement. Any expenses reimbursed by our clients are recognized as investment banking revenues. Revenues from financial advisory services primarily consist of fees generated in connection with merger, acquisition and restructuring transactions. Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Fees received prior to the completion of the transaction are deferred within accounts payable and accrued expenses on the consolidated statements of financial condition. Advisory fees from restructuring engagements are recognized over time using a time elapsed measure of progress as our clients simultaneously receive and consume the benefits of those services as they are provided. A significant portion of the fees we receive for our advisory services are considered variable as they are contingent upon a future event (e.g., completion of a transaction or third party emergence from bankruptcy) and are excluded from the transaction price until the uncertainty associated with the variable consideration is subsequently resolved, which is expected to occur upon achievement of the specified milestone. Payment for advisory services are generally due promptly upon completion of a specified milestone or, for retainer fees, periodically over the course of the engagement. We recognize a receivable between the date of completion of the milestone and payment by the customer. Expenses associated with investment banking advisory engagements are deferred only to the extent they are explicitly reimbursable by the client and the related revenue is recognized upon completion of services. All other investment banking advisory related expenses, including expenses incurred related to restructuring assignments, are expensed as incurred. All investment banking advisory expenses are recognized within other operating expenses on the consolidated statements of operations and any expenses reimbursed by our clients are recognized as investment banking revenues. Asset Management Fees. We earn management and performance fees in connection with investment advisory services provided to institutional and individual clients. Investment advisory fees are charged based on the value of assets in fee-based accounts and are affected by changes in the balances of client assets due to market fluctuations and levels of net new client assets. Fees are charged either in advance based on fixed rates applied to the value of the customers’ account at the beginning of the period or periodically based on contracted rates and account performance. Contracts can be terminated at any time with no incremental payments due to our company upon termination. If the contract is terminated by the customer fees are prorated for the period and fees charged for the post termination period are refundable to the customer. Disaggregation of Revenue The following tables present the Company’s revenues from contracts with customers by reportable segment disaggregated by major business activity and primary geographic regions for the three and nine months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 (1) Global Wealth Management Institutional Group Total Major business activity: Commissions $ 117,795 $ 40,220 $ 158,015 Investment banking - capital raising 7,722 85,553 93,275 Investment banking - advisory fees — 75,717 75,717 Asset management 200,735 8 200,743 Other 4,394 — 4,394 Total 330,646 201,498 532,144 Primary Geographic Region: United States 330,646 172,382 503,028 Europe — 28,197 28,197 Other — 919 919 $ 330,646 $ 201,498 $ 532,144 Nine Months Ended September 30, 2018 (1) Global Wealth Management Institutional Group Total Major business activity: Commissions $ 355,129 $ 135,563 $ 490,692 Investment banking - capital raising 23,378 222,666 246,044 Investment banking - advisory fees 81 260,312 260,393 Asset management 596,081 31 596,112 Other 11,908 — 11,908 Total 986,577 618,572 1,605,149 Primary Geographic Region: United States 986,577 522,147 1,508,724 Europe — 92,029 92,029 Other — 4,396 4,396 $ 986,577 $ 618,572 $ 1,605,149 (1) See Note 21 for further break-out of revenues by geography. Information on Remaining Performance Obligations and Revenue Recognized from Past Performance We do not disclose information about remaining performance obligations pertaining to contracts that have an original expected duration of one year or less. The transaction price allocated to remaining unsatisfied or partially unsatisfied performance obligations with an original expected duration exceeding one year was not material at September 30, 2018. Investment banking advisory fees that are contingent upon completion of a specific milestone and fees associated with certain distribution services are also excluded as the fees are considered variable and not included in the transaction price at September 30, 2018. Contract Balances The timing of our revenue recognition may differ from the timing of payment by our customers. We record a receivable when revenue is recognized prior to payment and we have an unconditional right to payment. Alternatively, when payment precedes the provision of the related services, we record deferred revenue until the performance obligations are satisfied. We had receivables related to revenues from contracts with customers of $146.7 million and $96.0 million at September 30, 2018 and December 31, 2017, respectively. We had no significant impairments related to these receivables during the three months ended September 30, 2018. Our deferred revenue primarily relates to retainer fees received in investment banking advisory engagements where the performance obligation has not yet been satisfied. Deferred revenue at September 30, 2018 was $10.2 million.

Interest Income And Interest Ex

Interest Income And Interest Expense	9 Months Ended
	Sep. 30, 2018
Banking And Thrift Interest [Abstract]
Interest Income And Interest Expense	NOTE 18 – Interest Income and Interest Expense The components of interest income and interest expense are as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Interest income: Bank loans, net $ 78,766 $ 54,006 $ 210,790 $ 147,495 Investment securities 66,825 48,072 185,263 136,123 Margin balances 13,066 9,919 36,322 27,124 Financial instruments owned 5,733 4,371 15,645 12,953 Other 5,370 1,494 13,895 4,071 $ 169,760 $ 117,862 $ 461,915 $ 327,766 Interest expense: Bank deposits $ 25,856 $ 4,770 $ 49,329 $ 8,424 Senior notes 11,248 8,655 33,488 24,935 Federal Home Loan Bank advances 4,232 1,255 10,579 5,771 Other 7,132 2,945 18,804 11,035 $ 48,468 $ 17,625 $ 112,200 $ 50,165

Employee Incentive, Deferred Co

Employee Incentive, Deferred Compensation, And Retirement Plans	9 Months Ended
	Sep. 30, 2018
Share Based Compensation Allocation And Classification In Financial Statements [Abstract]
Employee Incentive, Deferred Compensation, And Retirement Plans	NOTE 19 – Employee Incentive, Deferred Compensation, and Retirement Plans We maintain several incentive stock award plans that provide for the granting of stock options, stock appreciation rights, restricted stock, performance award, stock units and debentures to our employees. We are permitted to issue new shares under all stock award plans approved by shareholders or to reissue our treasury shares. Awards under our company’s incentive stock award plans are granted at market value at the date of grant. The awards generally vest ratably over a one- to ten-year vesting period. All stock-based compensation plans are administered by the Compensation Committee of the Board of Directors (“Compensation Committee”), which has the authority to interpret the plans, determine to whom awards may be granted under the plans, and determine the terms of each award. According to these plans, we are authorized to grant an additional 5.3 million shares at September 30, 2018. Stock-based compensation expense included in compensation and benefits expense in the consolidated statements of operations for our company’s incentive stock award plans was $31.7 million and $32.5 million for the three months ended September 30, 2018 and 2017, respectively, and $82.5 million and $98.1 million for the nine months ended September 30, 2018 and 2017, respectively. Restricted Stock Units and Restricted Stock Awards A restricted stock unit represents the right to receive a share of common stock from our company at a designated time in the future without cash payment by the employee and is issued in lieu of cash incentive, principally for deferred compensation and employee retention plans. The restricted stock units vest on an annual basis over the next one to ten years and are distributable, if vested, at future specified dates. Our Company grants Performance-based Restricted Stock Units (“PRSUs”) to its executive officers. Under the terms of the grants, the number of PRSUs that will vest and convert to shares will be based on the Company's achievement of the pre-determined performance objectives during the performance period. Any resulting delivery of shares for PRSUs granted as part of compensation will occur after four years for 80% of the earned award, and in the fifth year for the remaining 20% of the earned award. The number of shares converted has the potential to range from 0% to 200% based on how the Company performs during the performance period. Restricted stock awards are restricted as to sale or disposition. These restrictions lapse over the next one to five years. Compensation expense is amortized over the service period based on the fair value of the award on the grant date. The Company’s pre-determined performance objectives must be met for the awards to vest. Employees forfeit unvested share units upon termination of employment with a corresponding reversal of compensation expense. Certain restricted share units may continue to vest under certain circumstances as described in the Wealth Accumulation Plan (the "Plan"). At September 30, 2018, the total number of restricted stock units and restricted stock awards outstanding was 16.6 million, of which 12.9 million were unvested. At September 30, 2018, the total number of PRSUs was 0.6 million, of which all were unvested. At September 30, 2018, there was unrecognized compensation cost for stock units of approximately $292.2 million, which is expected to be recognized over a weighted-average period of 2.9 years. Deferred Compensation Plans The Plan is provided to certain revenue producers, officers, and key administrative employees, whereby a certain percentage of their incentive compensation is deferred as defined by the Plan into company stock units and debentures. Participants may elect to defer a portion of their incentive compensation. Deferred awards generally vest over a one- to ten-year period and are distributable upon vesting or at future specified dates. Deferred compensation costs are amortized on a straight-line basis over the vesting period. Elective deferrals are 100% vested. Additionally, the Plan allows Stifel’s financial advisors who achieve certain levels of production the option to defer a certain percentage of their gross commissions. As stipulated by the Plan, the financial advisors will defer 5% of their gross commissions. The mandatory deferral will be split evenly between company restricted stock units and a company fixed-rate cash debenture. They have the option to defer an additional 1% of gross commissions into company stock units with a 25% matching contribution. In addition, certain financial advisors, upon joining our company, may receive company stock units in lieu of transition cash payments. Deferred compensation related to these awards generally vests over a one- to eight-year period. Deferred compensation costs are amortized on a straight-line basis over the deferral period. Profit Sharing Plan Eligible employees of our company who have met certain service requirements may participate in the Stifel Financial Corp. Profit Sharing 401(k) Plan (the “401(k) Plan”). Employees are permitted within limitations imposed by tax law to make pre-tax contributions to the 401(k) Plan. We may match certain employee contributions or make additional contributions to the 401(k) Plan at our discretion. Our contributions to the 401(k) Plan were $3.4 million and $1.8 million for the three months ended September 30, 2018 and 2017, respectively and $10.1 million and $5.5 million for the nine months ended September 30, 2018 and 2017, respectively.

Off-Balance Sheet Credit Risk

Off-Balance Sheet Credit Risk	9 Months Ended
	Sep. 30, 2018
Concentration Risks Types No Concentration Percentage [Abstract]
Off-Balance Sheet Credit Risk	NOTE 20 – Off-Balance Sheet Credit Risk In the normal course of business, we execute, settle, and finance customer and proprietary securities transactions. These activities expose our company to off-balance sheet risk in the event that customers or other parties fail to satisfy their obligations. In accordance with industry practice, securities transactions generally settle within two business days after trade date. Should a customer or broker fail to deliver cash or securities as agreed, we may be required to purchase or sell securities at unfavorable market prices. We borrow and lend securities to facilitate the settlement process and finance transactions, utilizing customer margin securities held as collateral. We monitor the adequacy of collateral levels on a daily basis. We periodically borrow from banks on a collateralized basis, utilizing firm and customer margin securities in compliance with SEC rules. Should the counterparty fail to return customer securities pledged, we are subject to the risk of acquiring the securities at prevailing market prices in order to satisfy our customer obligations. We control our exposure to credit risk by continually monitoring our counterparties’ positions, and where deemed necessary, we may require a deposit of additional collateral and/or a reduction or diversification of positions. Our company sells securities it does not currently own (short sales) and is obligated to subsequently purchase such securities at prevailing market prices. We are exposed to risk of loss if securities prices increase prior to closing the transactions. We control our exposure to price risk from short sales through daily review and setting position and trading limits. We manage our risks associated with the aforementioned transactions through position and credit limits and the continuous monitoring of collateral. Additional collateral is required from customers and other counterparties when appropriate. We have accepted collateral in connection with resale agreements, securities borrowed transactions, and customer margin loans. Under many agreements, we are permitted to sell or repledge these securities held as collateral and use these securities to enter into securities lending arrangements or to deliver to counterparties to cover short positions. At September 30, 2018 and December 31, 2017, the fair value of securities accepted as collateral where we are permitted to sell or repledge the securities was $2.7 billion and $2.4 billion, respectively, and the fair value of the collateral that had been sold or repledged was $495.5 million and $233.7 million, respectively. We enter into interest rate derivative contracts to manage exposures that arise from business activities that result in the receipt or payment of future known and uncertain cash amounts, the value of which are determined by interest rates. Our derivative financial instruments are principally used to manage differences in the amount, timing, and duration of our known or expected cash payments related to certain variable-rate affiliated deposits. Interest rate swaps designated as cash flow hedges involve the receipt of variable-rate amounts from a counterparty in exchange for us making fixed-rate payments. Our interest rate hedging strategies may not work in all market environments and, as a result, may not be effective in mitigating interest rate risk. Derivatives’ notional contract amounts are not reflected as assets or liabilities in the consolidated statements of financial condition. Rather, the market or fair value of the derivative transactions are reported in the consolidated statements of financial condition as other assets or accounts payable and accrued expenses, as applicable. For a complete discussion of our activities related to derivative instruments, see Note 12 in the notes to consolidated financial statements. In the ordinary course of business, Stifel Bancorp has commitments to originate loans, standby letters of credit, and lines of credit. Commitments to originate loans are agreements to lend to a customer as long as there is no violation of any condition established by the contract. These commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since a portion of the commitments may expire without being drawn upon, the total commitment amounts do not necessarily represent future cash commitments. Each customer’s creditworthiness is evaluated on a case-by-case basis. The amount of collateral obtained, if necessary, is based on the credit evaluation of the counterparty. Collateral held varies, but may include accounts receivable, inventory, property, plant and equipment, commercial real estate, and residential real estate. At September 30, 2018 and December 31, 2017, Stifel Bancorp had outstanding commitments to originate loans aggregating $205.7 million and $160.2 million, respectively. The commitments extended over varying periods of time, with all commitments at September 30, 2018, scheduled to be disbursed in the following three months. Through Stifel Bancorp, in the normal course of business, we originate residential mortgage loans and sell them to investors. We may be required to repurchase mortgage loans that have been sold to investors in the event there are breaches of certain representations and warranties contained within the sales agreements. We may be required to repurchase mortgage loans that were sold to investors in the event that there was inadequate underwriting or fraud, or in the event that the loans become delinquent shortly after they are originated. We also may be required to indemnify certain purchasers and others against losses they incur in the event of breaches of representations and warranties and in various other circumstances, and the amount of such losses could exceed the repurchase amount of the related loans. Consequently, we may be exposed to credit risk associated with sold loans. Standby letters of credit are irrevocable conditional commitments issued by Stifel Bancorp to guarantee the performance of a customer to a third party. Financial standby letters of credit are primarily issued to support public and private borrowing arrangements, including commercial paper, bond financing, and similar transactions. Performance standby letters of credit are issued to guarantee performance of certain customers under non-financial contractual obligations. The credit risk involved in issuing standby letters of credit is essentially the same as that involved in extending loans to customers. Should Stifel Bancorp be obligated to perform under the standby letters of credit, it may seek recourse from the customer for reimbursement of amounts paid. At September 30, 2018 and December 31, 2017, Stifel Bancorp had outstanding letters of credit totaling $27.9 million and $82.5 million, respectively. A majority of the standby letters of credit commitments at September 30, 2018, have expiration terms that are less than one year. Lines of credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Lines of credit generally have fixed expiration dates. Stifel Bancorp uses the same credit policies in granting lines of credit as it does for on-balance sheet instruments. At September 30, 2018 and December 31, 2017, Stifel Bancorp had granted unused lines of credit to commercial and consumer borrowers aggregating $769.5 million and $590.5 million, respectively.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Segment Reporting	NOTE 21 – Segment Reporting We currently operate through the following three business segments: Global Wealth Management, Institutional Group, and various corporate activities combined in the Other segment. Our Global Wealth Management segment consists of two businesses, the Private Client Group and Stifel Bancorp, Inc. The Private Client Group includes branch offices and independent contractor offices of our broker-dealer subsidiaries located throughout the United States. These branches provide securities brokerage services, including the sale of equities, mutual funds, fixed income products, and insurance, as well as offering banking products to their clients through our bank subsidiaries, which provide residential, consumer, and commercial lending, as well as FDIC-insured deposit accounts to customers of our broker-dealer subsidiaries and to the general public. The Institutional Group segment includes institutional sales and trading. It provides securities brokerage, trading, and research services to institutions, with an emphasis on the sale of equity and fixed income products. This segment also includes the management of and participation in underwritings for both corporate and public finance (exclusive of sales credits generated through the private client group, which are included in the Global Wealth Management segment), merger and acquisition, and financial advisory services. The Other segment includes interest income from stock borrow activities, unallocated interest expense, interest income and gains and losses from investments held, amortization of stock-based awards, and all unallocated overhead cost associated with the execution of orders; processing of securities transactions; custody of client securities; receipt, identification, and delivery of funds and securities; compliance with regulatory and legal requirements; internal financial accounting and controls; and general administration and acquisition charges. Information concerning operations in these segments of business for the three and nine months ended September 30, 2018 and 2017 is as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net revenues: (1) Global Wealth Management $ 498,161 $ 453,558 $ 1,481,063 $ 1,348,280 Institutional Group 245,952 264,747 768,855 778,367 Other (5,771 ) 2,864 (18,486 ) (4,300 ) $ 738,342 $ 721,169 $ 2,231,432 $ 2,122,347 Income/(loss) before income taxes: Global Wealth Management $ 183,377 $ 161,756 $ 548,043 $ 457,045 Institutional Group 34,305 51,717 114,899 144,481 Other (77,152 ) (105,334 ) (284,511 ) (331,170 ) $ 140,530 $ 108,139 $ 378,431 $ 270,356 (1) No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2018 or 2017. The following table presents our company’s total assets on a segment basis at September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 December 31, 2017 Global Wealth Management $ 19,874,154 $ 17,717,617 Institutional Group 3,511,720 3,313,304 Other 374,174 353,032 $ 23,760,048 $ 21,383,953 We have operations in the United States, United Kingdom, Europe, and Asia. The Company’s foreign operations are conducted through its wholly owned subsidiary, SNEL. Substantially all long-lived assets are located in the United States. Revenues, classified by the major geographic areas in which they are earned for the three and nine months ended September 30, 2018 and 2017, were as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 United States $ 703,746 $ 680,505 $ 2,113,039 $ 2,017,999 United Kingdom 32,623 38,103 109,482 95,393 Other 1,973 2,561 8,911 8,955 $ 738,342 $ 721,169 $ 2,231,432 $ 2,122,347

Earnings Per Share ("EPS")

Earnings Per Share ("EPS")	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Earnings Per Share	NOTE 22 – Earnings Per Share (“EPS”) Basic EPS is computed by dividing earnings available to common shareholders by the weighted-average number of common shares outstanding. Diluted EPS reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock or resulted in the issuance of common stock that then shared in the earnings of the entity. Diluted earnings per share include dilutive stock options and stock units under the treasury stock method. The following table sets forth the computation of basic and diluted earnings per share for the three and nine months ended September 30, 2018 and 2017 (in thousands, except per share data) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income $ 103,858 $ 66,536 $ 279,906 $ 184,859 Preferred dividends 2,343 2,343 7,031 7,031 Net income available to common shareholders $ 101,515 $ 64,193 $ 272,875 $ 177,828 Shares for basic and diluted calculation: Average shares used in basic computation 71,919 68,522 71,824 68,488 Dilutive effect of stock options and units (1) 9,565 12,359 9,601 12,074 Average shares used in diluted computation 81,484 80,881 81,425 80,562 Earnings per common share: Basic $ 1.41 $ 0.94 $ 3.80 $ 2.60 Diluted $ 1.25 $ 0.79 $ 3.35 $ 2.21 (1) Diluted earnings per share is computed on the basis of the weighted-average number of shares of common stock plus the effect of dilutive potential common shares outstanding during the period using the treasury stock method. For the three and nine months ended September 30, 2018 and 2017, the anti-dilutive effect from restricted stock units was immaterial. Cash Dividends During the three and nine months ended September 30, 2018, we declared and paid cash dividends of $0.12 and $0.36 per common share. During the three and nine months ended September 30, 2017, we declared and paid cash dividends of $0.10 per common share.

Shareholders' Equity

Shareholders' Equity	9 Months Ended
	Sep. 30, 2018
Equity [Abstract]
Shareholders' Equity	NOTE 23 – Shareholders’ Equity Share Repurchase Program We have an ongoing authorization from the Board of Directors to repurchase our common stock in the open market or in negotiated transactions. At September 30, 2018, the maximum number of shares that may yet be purchased under this plan was 6.0 million. The repurchase program has no expiration date. These purchases may be made on the open market or in privately negotiated transactions, depending upon market conditions and other factors. Repurchased shares may be used to meet obligations under our employee benefit plans and for general corporate purposes. During the three months ended September 30, 2018, we repurchased $16.6 million, or 0.3 million shares using existing Board authorizations at an average price of $53.93 per share to meet obligations under our company’s employee benefit plans and for general corporate purposes. During the nine months ended September 30, 2018, we repurchased $62.5 million, or 1.1 million shares using existing Board authorizations at an average price of $55.66 per share to meet obligations under our company’s employee benefit plans and for general corporate purposes. There were no share repurchases during the three months ended September 30, 2017. During the nine months ended September 30, 2017, we repurchased $13.0 million, or 0.3 million shares using existing Board authorizations at an average price of $43.83 per share to meet obligations under our company’s employee benefit plans and for general corporate purposes. Issuance of Common Stock On August 31, 2018, we issued approximately 2.0 million shares for acquisition of Business Bancshares, Inc. During the nine months ended September 30, 2018, we issued 4.8 million shares, of which 1.1 million shares were reissued from treasury. Share issuances were primarily a result of the acquisition of Business Bancshares, Inc. and the vesting and exercise transactions under our incentive stock award plans.

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2018
Variable Interest Entity Not Primary Beneficiary Disclosures [Abstract]
Variable Interest Entities	NOTE 24 – Variable Interest Entities Our company’s involvement with VIEs is limited to entities used as investment vehicles and private equity funds, the establishment of Stifel Financial Capital Trusts, and our issuance of a convertible promissory note. We have formed several non-consolidated investment funds with third-party investors that are typically organized as limited liability companies (“LLCs”) or limited partnerships. These partnerships and LLCs have assets of $233.4 million at September 30, 2018. For those funds where we act as the general partner, our company’s economic interest is generally limited to management fee arrangements as stipulated by the fund operating agreements. We have generally provided the third-party investors with rights to terminate the funds or to remove us as the general partner. Management fee revenue earned by our company was insignificant during the three and nine months ended September 30, 2018 and 2017. In addition, our direct investment interest in these entities is insignificant at September 30, 2018 and December 31, 2017. Thomas Weisel Capital Management LLC, a subsidiary of our company, acts as the general partner of a series of investment funds in venture capital and fund of funds and manages investment funds that are active buyers of secondary interests in private equity funds, as well as portfolios of direct interests in venture-backed companies. These partnerships have combined assets of $285.5 million at September 30, 2018. We hold variable interests in these funds as a result of our company’s rights to receive management fees. Our company’s investment in and additional capital commitments to the private equity funds are also considered variable interests. The additional capital commitments are subject to call at a later date and are limited in amount. Our exposure to loss is limited to our investments in, advances and commitments to, and receivables due from these funds, and that exposure is insignificant at September 30, 2018. Management fee revenue earned by our company was insignificant during the three and nine months ended September 30, 2018 and 2017. For the entities noted above that were determined to be VIEs, we have concluded that we are not the primary beneficiary, and therefore, we are not required to consolidate these entities. Additionally, for certain other entities, we reviewed other relevant accounting guidance, which states the general partner in a limited partnership is presumed to control that limited partnership. The presumption may be overcome if the limited partners have either: (1) the substantive ability to dissolve the limited partnership or otherwise remove the general partner without cause, or (2) substantive participating rights, which provide the limited partners with the ability to effectively participate in significant decisions that would be expected to be made in the ordinary course of the limited partnership’s business and thereby preclude the general partner from exercising unilateral control over the partnership. If the criteria are not met, the consolidation of the partnership or limited liability company is required. Based on our evaluation of these entities, we determined that these entities do not require consolidation. Debenture to Stifel Financial Capital Trusts We have completed private placements of cumulative trust preferred securities through Stifel Financial Capital Trust II, Stifel Financial Capital Trust III, and Stifel Financial Capital Trust IV (collectively, the “Trusts”). The Trusts are non-consolidated wholly owned business trust subsidiaries of our company and were established for the limited purpose of issuing trust securities to third parties and lending the proceeds to our company. The trust preferred securities represent an indirect interest in junior subordinated debentures purchased from our company by the Trusts, and we effectively provide for the full and unconditional guarantee of the securities issued by the Trusts. We make timely payments of interest to the Trusts as required by contractual obligations, which are sufficient to cover payments due on the securities issued by the Trusts, and believe that it is unlikely that any circumstances would occur that would make it necessary for our company to make payments related to these Trusts other than those required under the terms of the debenture agreements and the trust preferred securities agreements. The Trusts were determined to be VIEs because the holders of the equity investment at risk do not have adequate decision-making ability over the Trust’s activities. Our investment in the Trusts is not a variable interest, because equity interests are variable interests only to the extent that the investment is considered to be at risk. Because our investment was funded by the Trusts, it is not considered to be at risk.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2018
Subsequent Events [Abstract]
Subsequent Events	NOTE 25 – Subsequent Events We evaluate subsequent events that have occurred after the balance sheet date but before the financial statements are issued. There are two types of subsequent events: (1) recognized, or those that provide additional evidence about conditions that existed at the date of the balance sheet, including the estimates inherent in the process of preparing financial statements, and (2) non-recognized, or those that provide evidence about conditions that did not exist at the date of the balance sheet but arose after that date. Based on the evaluation, we did not identify any recognized subsequent events that would have required adjustment to the consolidated financial statements.

Nature of Operations and Basi_2

Nature of Operations and Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature Of Operations	Nature of Operations Stifel Financial Corp. (the “Company”), through its wholly owned subsidiaries, is principally engaged in retail brokerage; securities trading; investment banking; investment advisory; retail, consumer, and commercial banking; and related financial services. We have offices throughout the United States and Europe. Our major geographic area of concentration is throughout the United States, with a growing presence in the United Kingdom and Europe. Our company’s principal customers are individual investors, corporations, municipalities, and institutions. On March 19, 2018, the Company completed the acquisition of Ziegler Wealth Management (“Ziegler”), a privately held investment bank, capital markets and proprietary investments firm that has 55 private client advisors in five states that manage approximately $5 billion in client assets. Ziegler provides its clients with capital raising, strategic advisory services, equity and fixed income sales & trading and research. The acquisition was funded with cash from operations. See Note 8 in the notes to consolidated financial statements for more details. On August 31, 2018, the Company completed the acquisition of Business Bancshares, Inc. (“BBI”) and its wholly owned subsidiary, The Business Bank of St. Louis, a full-service banking facility with approximately $600.0 million in assets that operates from a single location. Upon the closing of the transaction, the Business Bank of St. Louis was renamed “Stifel Bank” and Business Bancshares, Inc. was renamed “Stifel Bancorp, Inc.” Stifel Bancorp, Inc. (“Stifel Bancorp”) is the holding company for Stifel Bank & Trust, Stifel Bank, and their wholly owned subsidiaries. We issued approximately 2.0 million shares for acquisition of BBI. See Note 8 in the notes to consolidated financial statements for more details. Pro forma information is not presented, because the acquisition is not considered to be material, as defined by the SEC. The results of operations of Ziegler and Stifel Bancorp have been included in our results prospectively from the date of acquisition.
Basis Of Presentation	Basis of Presentation The consolidated financial statements include Stifel Financial Corp. and its wholly owned subsidiaries, principally Stifel, Nicolaus & Company, Incorporated (“Stifel”), Keefe, Bruyette & Woods, Inc., and Stifel Bancorp. All material intercompany balances and transactions have been eliminated. Unless otherwise indicated, the terms “we,” “us,” “our,” or “our company” in this report refer to Stifel Financial Corp. and its wholly owned subsidiaries. We have prepared the accompanying unaudited consolidated financial statements pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). Pursuant to these rules and regulations, we have omitted certain information and footnote disclosures we normally include in our annual consolidated financial statements prepared in accordance with U.S. generally accepted accounting principles. In management’s opinion, we have made all adjustments (consisting only of normal, recurring adjustments, except as otherwise noted) necessary to fairly present our financial position, results of operations and cash flows. Our interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. These financial statements and accompanying notes should be read in conjunction with the consolidated financial statements and the notes thereto in our Annual Report on Form 10-K for the year ended December 31, 2017 on file with the SEC. Certain amounts from prior periods have been reclassified to conform to the current period’s presentation. The effect of these reclassifications on our company’s previously reported consolidated financial statements was not material.
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies For a detailed discussion about the Company’s significant accounting policies, see Note 2, Summary of Significant Accounting Policies, in our consolidated financial statements included in Part II, Item 8 of our Annual Report on Form 10-K for the year ended December 31, 2017. Other than the following, there were no significant changes made to the Company’s significant accounting policies. The accounting policy changes are attributable to the adoption of the Financial Accounting Standards Board (“FASB”) Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (the “new revenue standard” or “ASU 2014-09”) on January 1, 2018. These revenue recognition policy updates are applied prospectively in our consolidated financial statements from January 1, 2018. Reported financial information for the historical comparable period was not revised and continues to be reported under the accounting standards in effect during the historical periods. The new revenue standard primarily impacts the following revenue recognition and presentation accounting policies of our company:
Investment Banking Revenues	Investment Banking Revenues Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Advisory expenses are deferred only to the extent they are explicitly reimbursable by the client and the related revenue is recognized at a point in time. All other investment banking advisory related expenses are expensed as incurred. Underwriting expenses are recognized as non-interest expense in the consolidated statements of operations and any expense reimbursements are recognized as investment banking revenues. See Note 2, New Accounting Pronouncements, and Note 17, Revenues from Contracts with Customers, for further information.

New Accounting Pronouncements (

New Accounting Pronouncements (Policies)	9 Months Ended
	Sep. 30, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Recently Adopted Accounting Guidance	Recently Adopted Accounting Guidance Comprehensive Income In February 2018, the FASB issued ASU 2018-02, “Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income” that provides for the reclassification from accumulated other comprehensive income to retained earnings for stranded effects resulting from the Tax Cuts and Jobs Act of 2017. The accounting update is effective for fiscal years beginning after December 15, 2018 and early adoption is permitted. We early adopted the guidance in the update on January 1, 2018. The adoption of the accounting update resulted in a reclassification adjustment of $3.0 million related to cash flow hedges and investment portfolio credit risk in our consolidated financial statements. Statement of Cash Flows In November 2016, the FASB issued ASU 2016-18, “Statement of Cash Flows (Topic 230) – Restricted Cash,” which adds or clarifies guidance on the classification and presentation of restricted cash in the statement of cash flows. The accounting update is effective for fiscal years beginning after December 15, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated statement of cash flows. Upon adoption of the accounting update, we recorded a decrease of $48.1 million in net cash provided by operating activities for the nine months ended September 30, 2017 related to reclassifying the changes in our cash segregated for regulatory purposes and restricted cash balance from operating activities to the cash and cash equivalent balances within the consolidated statements of cash flows. In August 2016, the FASB issued ASU 2016-15, “Statement of Cash Flows (Topic 230) – Classification of Certain Cash Receipts and Cash Payments,” which amends and clarifies the current guidance to reduce diversity in practice of the classification of certain cash receipts and payments in the consolidated statements of cash flows. The accounting update is effective for fiscal years beginning after December 31, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated statements of cash flows. Financial Assets and Financial Liabilities In January 2016, the FASB issued ASU 2016-01, “Financial Instruments – Recognition and Measurement of Financial Assets and Financial Liabilities” that will change the income statement impact of equity investments held by an entity, and the recognition of changes in fair value of financial liabilities when the fair value option is elected. The accounting update also amends certain disclosure requirements associated with the fair value of financial instruments. The accounting update is effective for fiscal years beginning after December 15, 2017. We adopted the guidance in the update on January 1, 2018. The adoption of the accounting update did not have a material impact on our consolidated financial statements. Revenue Recognition Effective January 1, 2018, the Company adopted ASU 2014-09, which provides accounting guidance on the recognition of revenues from contracts and requires gross presentation of certain costs that were previously offset against revenue. This change was applied prospectively from January 1, 2018 and there is no impact on our previously presented results. The adoption of the new revenue standard resulted in a reduction of beginning retained earnings of $3.9 million after-tax as a cumulative effect of adoption of an accounting change. The impact of adoption is primarily related to investment banking revenues that were previously recognized in prior periods, which are now being deferred under the new revenue standard. With the adoption of the new revenue recognition standard on January 1, 2018, capital raising and advisory fee revenues are no longer presented net of the related out-of-pocket deal expenses. As a result, capital raising and advisory fee revenues and other operating expenses are higher in the first nine months of 2018 by an identical $25.9 million, with no impact to net income. The scope of the accounting update does not apply to revenue associated with financial instruments, and as a result, will not have an impact on the elements of our consolidated statements of operations most closely associated with financial instruments, including principal transaction revenues, interest income, and interest expense. The new revenue standard primarily impacts the following revenue recognition and presentation accounting policies: Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Advisory expenses had historically been deferred until reimbursed by the client, the related fee revenue was recognized or the engagement was otherwise concluded. Under the new revenue standard, expenses are deferred only to the extent they are explicitly reimbursable by the client and the related revenue has been recognized. All other investment banking advisory related expenses, including expenses incurred related to restructuring assignments, are expensed as incurred. Underwriting expenses had historically been recorded net of client reimbursements and/or netted against revenues. Under the new revenue standard, all investment banking expenses will be recognized as non-interest expense in the consolidated statements of operations and any expense reimbursements will be recognized as investment banking revenues (i.e., expenses are no longer recorded net of client reimbursements and are not netted against revenues).
Recently Issued Accounting Guidance	Recently Issued Accounting Guidance Derivatives and Hedging In August 2017, the FASB issued ASU 2017-12, “Derivatives and Hedging (Topic 815) – Targeted Improvements to Accounting for Hedging Activities,” which amends the hedge accounting recognition and presentation requirements. The accounting update improves the transparency and understandability of information conveyed to financial statement users by better aligning companies’ hedging relationship to their existing risk management strategies, simplifies the application of hedge accounting and increases transparency regarding the scope and results of hedging program. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) and early adoption is permitted. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Callable Debt Securities In March 2017, the FASB issued ASU 2017-08, “Receivables – Nonrefundable Fees and Other Costs (Subtopic 310-20): Premium Amortization on Purchased Callable Debt Securities,” which shortens the amortization period for the premium on certain callable debt securities to the earliest call date. The amendments are applicable to any purchased individual debt security with an explicit and non-contingent call feature that is callable at a fixed price on a preset date. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) under a modified retrospective approach and early adoption is permitted. We are evaluating the impact the adoption of this new guidance will have on our consolidated financial statements. Goodwill Impairment Testing In January 2017, the FASB issued ASU 2017-04, “Intangibles – Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment,” which simplifies the subsequent measurement of goodwill and eliminates Step 2 from the goodwill impairment test. Under the accounting update, the annual, or interim, goodwill impairment test is performed by comparing the fair value of a reporting unit with its carrying amount, and an impairment charge should be recognized for the amount by which the carrying amount exceeds the reporting unit’s fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The accounting update is effective for annual or any interim impairment tests in fiscal years beginning after December 15, 2019 (January 1, 2020 for our company) and early adoption is permitted. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Financial Instruments – Credit Losses In June 2016, the FASB issued ASU 2016-13, “Financial Instruments − Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments.” This accounting update impacts the impairment model for certain financial assets measured at amortized cost by requiring a current expected credit loss (“CECL”) methodology to estimate expected credit losses over the entire life of the financial asset, recorded at inception or purchase. CECL will replace the loss model currently applicable to bank loans, held-to-maturity securities, and other receivables carried at amortized cost. The accounting update also eliminates the concept of other-than-temporary impairment for available-for-sale securities. Impairments on available-for-sale securities will be required to be recognized in earnings through an allowance, when the fair value is less than amortized cost and a credit loss exists or the securities are expected to be sold before recovery of amortized cost. Under the accounting update, there may be an ability to determine there are no expected credit losses in certain circumstances, e.g., based on collateral arrangements for lending and financing transactions or based on the credit quality of the borrower or issuer. Overall, the amendments in this accounting update are expected to accelerate the recognition of credit losses for portfolios where CECL models will be applied. The accounting update is effective for fiscal years beginning after December 15, 2019 (January 1, 2020 for our company) with early adoption permitted as of January 1, 2019. We are currently evaluating the impact of the accounting update, but the adoption is not expected to have a material impact on our consolidated financial statements. Leases In February 2016, the FASB issued ASU 2016-02, “Leases – (Topic 842)” that requires for leases longer than one year, a lessee recognize in the statements of financial condition a right-of-use asset, representing the right to use the underlying asset for the lease term, and a lease liability, representing the liability to make lease payments. The accounting update also requires that for finance leases, a lessee recognize interest expense on the lease liability, separately from the amortization of the right-of-use asset in the statements of earnings, while for operating leases, such amounts should be recognized as a combined expense. In addition, this accounting update requires expanded disclosures about the nature and terms of lease agreements. The accounting update is effective for fiscal years beginning after December 15, 2018 (January 1, 2019 for our company) under a modified retrospective approach and early adoption is permitted. The Company’s implementation efforts include reviewing existing leases and service contracts, which may include embedded leases. Upon adoption, our company expects a gross up on its consolidated statements of financial condition upon recognition of the right-of-use assets and lease liabilities and does not expect the amount of the gross up to have a material impact on its financial condition.
Revenue Recognition	Commissions. We earn commission revenue by executing, settling, and clearing transactions for clients primarily in OTC and listed equity securities, insurance products, and options. Trade execution and clearing and custody services, when provided together, represent a single performance obligation as the services are not separately identifiable in the context of the contract. Commission revenues associated with combined trade execution and clearing and custody services, as well as trade execution services on a standalone basis, are recognized at a point in time on trade-date. Commission revenues are generally paid on settlement date and we record a receivable between trade-date and payment on settlement date. Investment Banking. We provide our clients with a full range of capital markets and financial advisory services. Capital markets services include underwriting and placement agent services in both the equity and debt capital markets, including private equity placements, initial public offerings, follow-on offerings, underwriting and distributing public and private debt. Capital raising revenues are recognized at a point in time on trade-date, as the client obtains the control and benefit of the capital markets offering at that point. Costs associated with capital raising transactions are deferred until the related revenue is recognized or the engagement is otherwise concluded, and are recorded on a gross basis within other operating expenses in the consolidated statements of operations as we are acting as a principal in the arrangement. Any expenses reimbursed by our clients are recognized as investment banking revenues. Revenues from financial advisory services primarily consist of fees generated in connection with merger, acquisition and restructuring transactions. Advisory fees from mergers and acquisitions engagements are recognized at a point in time when the related transaction is completed, as the performance obligation is to successfully broker a specific transaction. Fees received prior to the completion of the transaction are deferred within accounts payable and accrued expenses on the consolidated statements of financial condition. Advisory fees from restructuring engagements are recognized over time using a time elapsed measure of progress as our clients simultaneously receive and consume the benefits of those services as they are provided. A significant portion of the fees we receive for our advisory services are considered variable as they are contingent upon a future event (e.g., completion of a transaction or third party emergence from bankruptcy) and are excluded from the transaction price until the uncertainty associated with the variable consideration is subsequently resolved, which is expected to occur upon achievement of the specified milestone. Payment for advisory services are generally due promptly upon completion of a specified milestone or, for retainer fees, periodically over the course of the engagement. We recognize a receivable between the date of completion of the milestone and payment by the customer. Expenses associated with investment banking advisory engagements are deferred only to the extent they are explicitly reimbursable by the client and the related revenue is recognized upon completion of services. All other investment banking advisory related expenses, including expenses incurred related to restructuring assignments, are expensed as incurred. All investment banking advisory expenses are recognized within other operating expenses on the consolidated statements of operations and any expenses reimbursed by our clients are recognized as investment banking revenues. Asset Management Fees. We earn management and performance fees in connection with investment advisory services provided to institutional and individual clients. Investment advisory fees are charged based on the value of assets in fee-based accounts and are affected by changes in the balances of client assets due to market fluctuations and levels of net new client assets. Fees are charged either in advance based on fixed rates applied to the value of the customers’ account at the beginning of the period or periodically based on contracted rates and account performance. Contracts can be terminated at any time with no incremental payments due to our company upon termination. If the contract is terminated by the customer fees are prorated for the period and fees charged for the post termination period are refundable to the customer.

Receivables From And Payables_2

Receivables From And Payables To Brokers, Dealers And Clearing Organizations (Tables)	9 Months Ended
	Sep. 30, 2018
Due To And From Broker Dealers And Clearing Organizations [Abstract]
Amounts Receivable From Brokers, Dealers, And Clearing Organizations	Amounts receivable from brokers, dealers, and clearing organizations at September 30, 2018 and December 31, 2017, included (in thousands) September 30, 2018 December 31, 2017 Receivables from clearing organizations $ 440,154 $ 270,285 Deposits paid for securities borrowed 170,165 132,776 Securities failed to deliver 35,801 56,046 $ 646,120 $ 459,107
Amounts Payable To Brokers, Dealers, And Clearing Organizations	Amounts payable to brokers, dealers, and clearing organizations at September 30, 2018 and December 31, 2017, included (in thousands) September 30, 2018 December 31, 2017 Deposits received from securities loaned $ 691,150 $ 219,782 Payable to clearing organizations 201,510 27,223 Securities failed to receive 35,472 29,297 $ 928,132 $ 276,302

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Schedule Of Fair Value Of Investments In And Unfunded Commitments To Funds Measured At Net Asset Value	September 30, 2018 Fair value of investments Unfunded commitments Money market funds $ 18,696 $ — Mutual funds 10,506 — Private equity funds 3,394 1,535 Partnership interests 4,405 1,324 Total $ 37,001 $ 2,859 December 31, 2017 Fair value of investments Unfunded commitments Money market funds $ 77,441 $ — Mutual funds 11,748 — Private equity funds 7,677 1,825 Partnership interests 5,124 1,330 Total $ 101,990 $ 3,155
Fair Value Of Assets And Liabilities Measured On Recurring Basis	September 30, 2018 Total Level 1 Level 2 Level 3 Financial instruments owned: U.S. government securities $ 36,214 $ 36,214 $ — $ — U.S. government agency securities 167,886 — 167,886 — Mortgage-backed securities: Agency 380,044 — 380,044 — Non-agency 23,747 — 23,746 1 Asset-backed securities 29,806 — 29,451 355 Corporate securities: Fixed income securities 290,627 262 290,365 — Equity securities 69,205 68,892 212 101 Sovereign debt 15,996 — 15,996 — State and municipal securities 149,207 — 149,207 — Total financial instruments owned 1,162,732 105,368 1,056,907 457 Available-for-sale securities: U.S. government agency securities 5,165 516 4,649 — State and municipal securities 68,876 — 68,876 — Mortgage-backed securities: Agency 250,808 — 250,808 — Commercial 68,823 — 68,823 — Non-agency 1,269 — 1,269 — Corporate fixed income securities 1,177,315 — 1,177,315 — Asset-backed securities 1,777,351 — 1,777,351 — Total available-for-sale securities 3,349,607 516 3,349,091 — Investments: Corporate equity securities 42,495 42,495 — — Auction rate securities: Equity securities 16,525 — — 16,525 Municipal securities 799 — — 799 Other 1,046 — 189 857 Investments in funds measured at NAV 18,305 Total investments 79,170 42,495 189 18,181 Cash equivalents measured at NAV 18,696 Derivative contracts (1) 11,117 11,117 $ 4,621,322 $ 148,379 $ 4,417,304 $ 18,638 (1) September 30, 2018 Total Level 1 Level 2 Level 3 Liabilities: Financial instruments sold, but not yet purchased: U.S. government securities $ 512,275 $ 512,275 $ — $ — Mortgage-backed securities: Agency 95,312 — 95,312 — Corporate securities: Fixed income securities 213,335 96 213,239 — Equity securities 78,895 78,895 — — Sovereign debt 11,557 — 11,557 — Total financial instruments sold, but not yet purchased $ 911,374 $ 591,266 $ 320,108 $ — Assets and liabilities measured at fair value on a recurring basis as of December 31, 2017, are presented below (in thousands) December 31, 2017 Total Level 1 Level 2 Level 3 Financial instruments owned: U.S. government securities $ 13,466 $ 13,466 $ — $ — U.S. government agency securities 147,223 — 147,223 — Mortgage-backed securities: Agency 302,445 — 302,445 — Non-agency 29,356 — 29,355 1 Asset-backed securities 76,752 — 76,395 357 Corporate securities: Fixed income securities 325,471 362 324,867 242 Equity securities 46,802 46,411 138 253 Sovereign debt 32,470 — 32,470 — State and municipal securities 169,699 — 169,699 — Total financial instruments owned 1,143,684 60,239 1,082,592 853 Available-for-sale securities: U.S. government agency securities 4,983 516 4,467 — State and municipal securities 70,559 — 70,559 — Mortgage-backed securities: Agency 305,530 — 305,530 — Commercial 72,488 — 72,488 — Non-agency 1,568 — 1,568 — Corporate fixed income securities 1,211,442 — 1,211,442 — Asset-backed securities 2,106,938 — 2,106,938 — Total available-for-sale securities 3,773,508 516 3,772,992 — Investments: Corporate equity securities 49,978 49,978 — — Auction rate securities: Equity securities 34,789 — — 34,789 Municipal securities 846 — — 846 Other 1,217 — 360 857 Investments measured at NAV 24,549 Total investments 111,379 49,978 360 36,492 Cash equivalents measured at NAV 77,441 Derivative contracts (1) 7,995 — 7,995 — $ 5,114,007 $ 110,733 $ 4,863,939 $ 37,345 (1) December 31, 2017 Total Level 1 Level 2 Level 3 Liabilities: Financial instruments sold, but not yet purchased: U.S. government securities $ 442,402 $ 442,402 $ — $ — U.S. government agency securities 10,348 — 10,348 — Mortgage-backed securities: Agency 86,612 — 86,612 — Corporate securities: Fixed income securities 180,755 — 180,755 — Equity securities 38,510 38,070 440 — Sovereign debt 20,236 — 20,236 — Total financial instruments sold, but not yet purchased $ 778,863 $ 480,472 $ 298,391 $ —
Schedule Of Changes In Fair Value Associated With Level 3 Financial Instruments	Three Months Ended September 30, 2018 Financial instruments owned Investments Mortgage- Backed Securities – Non-Agency Asset-Backed Securities Equity Securities Auction Securities – Equity Auction Rate Securities – Municipal Other Balance at June 30, 2018 $ 1 $ 355 $ 123 $ 25,303 $ 846 $ 857 Unrealized gains/(losses): Included in changes in net assets (1) — — — 997 3 — Realized gains/(losses) (1) — — (22 ) — — — Purchases — — — — — — Sales — — — — — — Redemptions — — — (9,775 ) (50 ) — Transfers: Into Level 3 — — — — — — Out of Level 3 — — — — — — Net change — — (22 ) (8,778 ) (47 ) — Balance at September 30, 2018 $ 1 $ 355 $ 101 $ 16,525 $ 799 $ 857 (1) Realized and unrealized gains/(losses) related to financial instruments owned and investments are reported in other income in the consolidated statements of operations. Nine Months Ended September 30, 2018 Financial instruments owned Investments Mortgage- Backed Securities – Non-Agency Asset-Backed Securities Fixed Income Securities Equity Securities Auction Securities – Equity Auction Rate Securities – Municipal Other Balance at December 31, 2017 $ 1 $ 357 $ 242 $ 253 $ 34,789 $ 846 $ 857 Unrealized gains/(losses): Included in changes in net assets (1) — 3 — (130 ) 1,086 3 — Realized gains/(losses) (1) — — — (22 ) — — — Purchases — — — — — — — Sales — — — — — — — Redemptions — (5 ) (242 ) — (19,350 ) (50 ) — Transfers: Into Level 3 — — — — — — — Out of Level 3 — — — — — — — Net change — (2 ) (242 ) (152 ) (18,264 ) (47 ) — Balance at September 30, 2018 $ 1 $ 355 $ — $ 101 $ 16,525 $ 799 $ 857 (1) Realized and unrealized gains/(losses) related to financial instruments owned and investments are reported in other income in the consolidated statements of operations.
Quantitative Information Related To The Significant Unobservable Inputs Utilized In Level 3 Recurring Fair Value Measurements	Valuation technique Unobservable input Range Weighted average Investments: Auction rate securities: Equity securities Discounted cash flow Discount rate 0.6% - 6.5% 3.8% Workout period 2-3 years 2.4 years Municipal securities Discounted cash flow Discount rate 0.5% - 9.9% 3.2% Workout period 1-4 years 2.0 years
Schedule Of Fair Value Of Financial Instruments	September 30, 2018 December 31, 2017 Carrying Value Estimated Fair Value Carrying Value Estimated Fair Value Financial assets: Cash and cash equivalents $ 694,302 $ 694,302 $ 696,283 $ 696,283 Cash segregated for regulatory purposes 21,585 21,585 90,802 90,802 Securities purchased under agreements to resell 622,361 622,361 512,220 512,220 Financial instruments owned 1,162,732 1,162,732 1,143,684 1,143,684 Available-for-sale securities 3,349,607 3,349,607 3,773,508 3,773,508 Held-to-maturity securities 4,565,453 4,506,385 3,698,098 3,710,478 Loans held for sale 262,063 262,063 226,068 226,068 Bank loans 8,253,989 8,330,974 6,947,759 6,953,328 Investments 79,170 79,170 111,379 111,379 Derivative contracts (1) 11,117 11,117 7,995 7,995 Financial liabilities: Securities sold under agreements to repurchase $ 495,484 $ 495,484 $ 233,704 $ 233,704 Bank deposits 14,502,952 13,711,447 13,411,935 12,702,746 Financial instruments sold, but not yet purchased 911,374 911,374 778,863 778,863 Federal Home Loan Bank advances 1,064,000 1,064,000 745,000 745,000 Borrowings 140,030 140,030 256,000 256,000 Senior notes 1,015,714 1,012,374 1,014,940 1,044,768 Debentures to Stifel Financial Capital Trusts 67,500 68,839 67,500 64,962 (1)
Estimated Fair Values Of Financial Instruments Not Measured At Fair Value	September 30, 2018 Total Level 1 Level 2 Level 3 Financial assets: Cash $ 675,606 $ 675,606 $ — $ — Cash segregated for regulatory purposes 21,585 21,585 — — Securities purchased under agreements to resell 622,361 586,829 35,532 — Held-to-maturity securities 4,506,385 — 4,345,021 161,364 Loans held for sale 262,063 — 262,063 — Bank loans 8,330,974 — 8,330,974 — Financial liabilities: Securities sold under agreements to repurchase $ 495,484 $ 126,378 $ 369,106 $ — Bank deposits 13,711,447 — 13,711,447 — Federal Home Loan Bank advances 1,064,000 1,064,000 — — Borrowings 140,030 140,030 — — Senior notes 1,012,374 1,012,374 — — Debentures to Stifel Financial Capital Trusts 68,839 — — 68,839 December 31, 2017 Total Level 1 Level 2 Level 3 Financial assets: Cash $ 618,842 $ 618,842 $ — $ — Cash segregated for regulatory purposes 90,802 90,802 — — Securities purchased under agreements to resell 512,220 428,740 83,480 — Held-to-maturity securities 3,710,478 — 3,517,781 192,697 Loans held for sale 226,068 — 226,068 — Bank loans 6,953,328 — 6,953,328 — Financial liabilities: Securities sold under agreements to repurchase $ 233,704 $ 92,278 $ 141,426 $ — Bank deposits 12,702,746 — 12,702,746 — Federal Home Loan Bank advances 745,000 745,000 — — Borrowings 256,000 256,000 — — Senior notes 1,044,768 1,044,768 — — Debentures to Stifel Financial Capital Trusts 64,962 — — 64,962

Financial Instruments Owned A_2

Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased (Tables)	9 Months Ended
	Sep. 30, 2018
Investments Debt And Equity Securities [Abstract]
Components Of Trading Securities Owned And Trading Securities Sold, But Not Yet Purchased	The components of financial instruments owned and financial instruments sold, but not yet purchased, at September 30, 2018 and December 31, 2017 are as follows (in thousands) September 30, 2018 December 31, 2017 Financial instruments owned: U.S. government securities $ 36,214 $ 13,466 U.S. government agency securities 167,886 147,223 Mortgage-backed securities: Agency 380,044 302,445 Non-agency 23,747 29,356 Asset-backed securities 29,806 76,752 Corporate securities: Fixed income securities 290,627 325,471 Equity securities 69,205 46,802 Sovereign debt 15,996 32,470 State and municipal securities 149,207 169,699 $ 1,162,732 $ 1,143,684 Financial instruments sold, but not yet purchased: U.S. government securities $ 512,275 $ 442,402 U.S. government agency securities — 10,348 Mortgage-backed securities: Agency 95,312 86,612 Corporate securities: Fixed income securities 213,335 180,755 Equity securities 78,895 38,510 Sovereign debt 11,557 20,236 $ 911,374 $ 778,863

Available-For-Sale And Held-T_2

Available-For-Sale And Held-To-Maturity Securities (Tables)	9 Months Ended
	Sep. 30, 2018
Investments Debt And Equity Securities [Abstract]
Schedule Of Amortized Cost And Fair Values Of Available For Sale Securities And Held To Maturity Securities	The following tables provide a summary of the amortized cost and fair values of the available-for-sale securities and held-to-maturity securities at September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 Amortized Cost Gross Unrealized Gains (1) Gross Unrealized Losses (1) Estimated Fair Value Available-for-sale securities U.S. government agency securities $ 5,226 $ — $ (61 ) $ 5,165 State and municipal securities 73,253 — (4,377 ) 68,876 Mortgage-backed securities: Agency 256,120 29 (5,341 ) 250,808 Commercial 74,698 8 (5,883 ) 68,823 Non-agency 1,281 — (12 ) 1,269 Corporate fixed income securities 1,200,498 2,542 (25,725 ) 1,177,315 Asset-backed securities 1,782,052 3,109 (7,810 ) 1,777,351 $ 3,393,128 $ 5,688 $ (49,209 ) $ 3,349,607 Held-to-maturity securities (2) Mortgage-backed securities: Agency $ 1,244,582 $ — $ (48,907 ) $ 1,195,675 Commercial 55,351 — (343 ) 55,008 Asset-backed securities 3,265,520 4,940 (14,758 ) 3,255,702 $ 4,565,453 $ 4,940 $ (64,008 ) $ 4,506,385 December 31, 2017 Amortized Cost Gross Unrealized Gains (1) Gross Unrealized Losses (1) Estimated Fair Value Available-for-sale securities U.S. government agency securities $ 5,022 $ — $ (39 ) $ 4,983 State and municipal securities 74,691 — (4,132 ) 70,559 Mortgage-backed securities: Agency 308,409 102 (2,981 ) 305,530 Commercial 75,548 28 (3,088 ) 72,488 Non-agency 1,568 — — 1,568 Corporate fixed income securities 1,213,262 3,832 (5,652 ) 1,211,442 Asset-backed securities 2,098,958 12,877 (4,897 ) 2,106,938 $ 3,777,458 $ 16,839 $ (20,789 ) $ 3,773,508 Held-to-maturity securities (2) Mortgage-backed securities: Agency $ 1,334,833 $ 13,621 $ (16,208 ) $ 1,332,246 Commercial 58,971 1,313 — 60,284 Asset-backed securities 2,264,283 15,526 (1,862 ) 2,277,947 Corporate fixed income securities 40,011 27 (37 ) 40,001 $ 3,698,098 $ 30,487 $ (18,107 ) $ 3,710,478 (1) Unrealized gains/(losses) related to available-for-sale securities are reported in accumulated other comprehensive loss. (2) Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.
Schedule Of Amortized Cost And Fair Values Of Debt Securities By Contractual Maturity	The table below summarizes the amortized cost and fair values of debt securities by contractual maturity. Expected maturities may differ significantly from contractual maturities, as issuers may have the right to call or prepay obligations with or without call or prepayment penalties. September 30, 2018 Available-for-sale securities Held-to-maturity securities Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Debt securities Within one year $ 37,338 $ 37,275 $ — $ — After one year through three years 380,761 372,133 — — After three years through five years 351,855 345,895 — — After five years through ten years 698,866 689,934 478,024 478,491 After ten years 1,592,209 1,583,470 2,787,496 2,777,211 Mortgage-backed securities After one year through three years 163 163 55,351 55,008 After three years through five years 1,360 1,365 — — After five years through ten years 6,242 6,194 180,433 173,389 After ten years 324,334 313,178 1,064,149 1,022,286 $ 3,393,128 $ 3,349,607 $ 4,565,453 $ 4,506,385
Contractual Maturities	The maturities of our available-for-sale (fair value) and held-to-maturity (amortized cost) securities at September 30, 2018, are as follows ( in thousands Within 1 Year 1-5 Years 5-10 Years After 10 Years Total Available-for-sale: (1) U.S. government agency securities $ 1,657 $ 3,508 $ — $ — $ 5,165 State and municipal securities 395 — 18,272 50,209 68,876 Mortgage-backed securities: Agency — 1,528 6,194 243,086 250,808 Commercial — — — 68,823 68,823 Non-agency — — — 1,269 1,269 Corporate fixed income securities 35,223 714,520 427,572 — 1,177,315 Asset-backed securities — — 244,090 1,533,261 1,777,351 $ 37,275 $ 719,556 $ 696,128 $ 1,896,648 $ 3,349,607 Held-to-maturity: Mortgage-backed securities: Agency $ — $ — $ 180,433 $ 1,064,149 $ 1,244,582 Commercial — 55,351 — — 55,351 Asset-backed securities — — 478,024 2,787,496 3,265,520 $ — $ 55,351 $ 658,457 $ 3,851,645 $ 4,565,453 (1) Due to the immaterial amount of income recognized on tax-exempt securities, yields were not calculated on a tax-equivalent basis.
Schedule Of Gross Unrealized Losses And The Estimated Fair Value By Length Of Time	The following table shows the gross unrealized losses and fair value of the Company’s investment securities with unrealized losses, aggregated by investment category and length of time the individual investment securities have been in continuous unrealized loss positions, at September 30, 2018 (in thousands) Less than 12 months 12 months or more Total Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Gross Unrealized Losses Estimated Fair Value Available-for-sale securities U.S. government securities $ (61 ) $ 5,040 $ — $ — $ (61 ) $ 5,040 State and municipal securities — — (4,377 ) 68,481 (4,377 ) 68,481 Mortgage-backed securities: Agency (731 ) 40,606 (4,610 ) 188,110 (5,341 ) 228,716 Commercial — — (5,883 ) 67,841 (5,883 ) 67,841 Non-agency (12 ) 1,261 — — (12 ) 1,261 Corporate fixed income securities (14,053 ) 565,671 (11,672 ) 310,351 (25,725 ) 876,022 Asset-backed securities (7,810 ) 517,276 — — (7,810 ) 517,276 $ (22,667 ) $ 1,129,854 $ (26,542 ) $ 634,783 $ (49,209 ) $ 1,764,637 Held-to-maturity securities Mortgage-backed securities: Agency $ (11,804 ) $ 556,381 $ (37,103 ) $ 639,295 $ (48,907 ) $ 1,195,676 Commercial (343 ) 55,008 — — (343 ) 55,008 Asset-backed securities (12,298 ) 1,675,810 (2,460 ) 42,507 (14,758 ) 1,718,317 $ (24,445 ) $ 2,287,199 $ (39,563 ) $ 681,802 $ (64,008 ) $ 2,969,001

Bank Loans (Tables)

Bank Loans (Tables)	9 Months Ended
	Sep. 30, 2018
Receivables [Abstract]
Schedule Of Balance And Associated Percentage Of Each Major Loan Category In Bank Loan Portfolio	September 30, 2018 December 31, 2017 Balance Percent Balance Percent Commercial and industrial $ 3,127,435 37.5 % $ 2,437,938 34.8 % Residential real estate 2,792,269 33.5 2,593,576 37.0 Securities-based loans 1,836,450 22.0 1,819,206 25.9 Commercial real estate 328,814 3.9 116,258 1.7 Construction and land 120,969 1.4 7,896 0.1 Home equity lines of credit 29,118 0.3 15,039 0.2 Other 109,571 1.4 24,508 0.3 Gross bank loans 8,344,626 100.0 % 7,014,421 100.0 % Unamortized loan premium/(discount), net (13,419 ) 788 Loans in process (2,755 ) (856 ) Unamortized loan fees, net 6,237 872 Allowance for loan losses (80,700 ) (67,466 ) Bank loans, net $ 8,253,989 $ 6,947,759
Activity In The Allowance For Loan Losses By Portfolio Segment	Three Months Ended September 30, 2018 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 59,572 $ 5,008 $ — $ — $ 64,580 Residential real estate 9,328 1,165 — — 10,493 Securities-based loans 1,928 (5 ) — — 1,923 Commercial real estate 1,672 90 — — 1,762 Construction and land 303 600 — — 903 Home equity lines of credit 229 — — — 229 Other 13 (3 ) — 1 11 Qualitative 730 69 — — 799 $ 73,775 $ 6,924 $ — $ 1 $ 80,700 Nine Months Ended September 30, 2018 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 54,474 $ 10,118 $ (12 ) $ — $ 64,580 Residential real estate 8,430 2,063 — — 10,493 Securities-based loans 2,088 (165 ) — — 1,923 Commercial real estate 1,520 242 — — 1,762 Construction and land 100 803 — — 903 Home equity lines of credit 162 65 — 2 229 Other 16 (5 ) (2 ) 2 11 Qualitative 676 123 — — 799 $ 67,466 $ 13,244 $ (14 ) $ 4 $ 80,700 Three Months Ended September 30, 2017 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 40,805 $ 6,312 $ — $ 35 $ 47,152 Residential real estate 5,569 1,566 — — 7,135 Securities-based loans 3,600 (288 ) — — 3,312 Commercial real estate 932 95 — — 1,027 Home equity lines of credit 283 (13 ) — 1 271 Construction and land 224 9 — — 233 Other 105 (3 ) — 1 103 Qualitative 2,684 312 — — 2,996 $ 54,202 $ 7,990 $ — $ 37 $ 62,229 Nine Months Ended September 30, 2017 Beginning Balance Provision Charge-offs Recoveries Ending Balance Commercial and industrial $ 35,127 $ 12,239 $ (250 ) $ 36 $ 47,152 Residential real estate 2,660 4,475 — — 7,135 Securities-based loans 3,094 218 — — 3,312 Commercial real estate 1,363 2,367 (2,703 ) — 1,027 Home equity lines of credit 371 (102 ) — 2 271 Construction and land 232 1 — — 233 Other 129 (27 ) — 1 103 Qualitative 2,187 809 — — 2,996 $ 45,163 $ 19,980 $ (2,953 ) $ 39 $ 62,229
Recorded Balance Of Loans And Amount Of Allowance Allocated Based Upon Impairment Method By Portfolio Segment	Allowance for Loan Losses Recorded Investment in Loans Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Commercial and industrial $ 8,677 $ 55,903 $ 64,580 $ 23,630 $ 3,103,805 $ 3,127,435 Residential real estate 24 10,469 10,493 328 2,791,941 2,792,269 Securities-based loans — 1,923 1,923 — 1,836,450 1,836,450 Commercial real estate — 1,762 1,762 — 328,814 328,814 Construction and land — 903 903 — 120,969 120,969 Home equity lines of credit — 229 229 231 28,887 29,118 Other — 11 11 58 109,513 109,571 Qualitative — 799 799 — — — $ 8,701 $ 71,999 $ 80,700 $ 24,247 $ 8,320,379 $ 8,344,626 Allowance for Loan Losses Recorded Investment in Loans Individually Evaluated Impairment Collectively Evaluated for Impairment Total Individually Evaluated for Impairment Collectively Evaluated for Impairment Total Residential real estate $ 24 $ 8,406 $ 8,430 $ 171 $ 2,593,405 $ 2,593,576 Commercial and industrial 9,059 45,415 54,474 28,856 2,409,082 2,437,938 Securities-based loans — 2,088 2,088 — 1,819,206 1,819,206 Commercial real estate — 1,520 1,520 — 116,258 116,258 Home equity lines of credit 20 142 162 184 14,855 15,039 Construction and land — 100 100 — 7,896 7,896 Other 2 14 16 2 24,506 24,508 Qualitative — 676 676 — — — $ 9,105 $ 58,361 $ 67,466 $ 29,213 $ 6,985,208 $ 7,014,421
Loans That Were Individually Evaluated For Impairment By Portfolio Segment	September 30, 2018 Unpaid Contractual Principal Balance Recorded Investment with No Allowance Recorded Investment with Allowance Total Recorded Investment Related Allowance Average Recorded Investment Commercial and industrial $ 23,630 $ 196 $ 23,434 $ 23,630 $ 8,677 $ 23,783 Residential real estate 353 80 248 328 24 355 Home equity lines of credit 231 184 47 231 — 236 Other 731 26 32 58 — 60 Total $ 24,945 $ 486 $ 23,761 $ 24,247 $ 8,701 $ 24,434 December 31, 2017 Unpaid Contractual Principal Balance Recorded Investment with No Allowance Recorded Investment with Allowance Total Recorded Investment Related Allowance Average Recorded Investment Commercial and industrial $ 28,856 $ 5,211 $ 23,645 $ 28,856 $ 9,059 $ 30,277 Home equity lines of credit 184 — 184 184 20 300 Residential real estate 171 — 171 171 24 174 Other 677 — 2 2 2 5 Total $ 29,888 $ 5,211 $ 24,002 $ 29,213 $ 9,105 $ 30,756
Aging Of The Recorded Investment In Past Due Loans	As of September 30, 2018 30 – 89 Days Past Due 90 or More Days Past Due Total Due Current Balance Total Commercial and industrial $ — $ 14,656 $ 14,656 $ 3,112,779 $ 3,127,435 Residential real estate 3,745 184 3,929 2,788,340 2,792,269 Securities-based loans — — — 1,836,450 1,836,450 Commercial real estate — — — 328,814 328,814 Construction and land — — — 120,969 120,969 Home equity lines of credit 47 — 47 29,071 29,118 Other — 67 67 109,504 109,571 Total $ 3,792 $ 14,907 $ 18,699 $ 8,325,927 $ 8,344,626 As of September 30, 2018* Non-Accrual Restructured Total Commercial and industrial $ 14,694 $ 8,936 $ 23,630 Residential real estate 159 169 328 Home equity lines of credit 231 — 231 Other 58 — 58 Total $ 15,142 $ 9,105 $ 24,247 * There were no loans past due 90 days and still accruing interest at September 30, 2018. As of December 31, 2017 30 – 89 Days Past Due 90 or More Days Past Due Total Past Due Current Balance Total Residential real estate $ 7,892 $ — $ 7,892 $ 2,585,684 $ 2,593,576 Commercial and industrial 11,883 — 11,883 2,426,055 2,437,938 Securities-based loans — — — 1,819,206 1,819,206 Commercial real estate — — — 116,258 116,258 Home equity lines of credit 184 — 184 14,855 15,039 Construction and land — — — 7,896 7,896 Other 2 — 2 24,506 24,508 Total $ 19,961 $ — $ 19,961 $ 6,994,460 $ 7,014,421 As of December 31, 2017* Non-Accrual Restructured Total Commercial and industrial $ 19,904 $ 8,952 $ 28,856 Home equity lines of credit 184 — 184 Residential real estate — 171 171 Other 2 — 2 Total $ 20,090 $ 9,123 $ 29,213 * There were no loans past due 90 days and still accruing interest at December 31, 2017.
Risk Category Of Loan Portfolio	As of September 30, 2018 Pass Special Substandard Doubtful Total Commercial and industrial $ 3,069,237 $ 34,488 $ 23,710 $ — $ 3,127,435 Residential real estate 2,791,627 394 248 — 2,792,269 Securities-based loans 1,836,450 — — — 1,836,450 Commercial real estate 328,814 — — — 328,814 Construction and land 120,969 — — — 120,969 Home equity lines of credit 28,887 — 231 — 29,118 Other 109,513 — 47 11 109,571 Total $ 8,285,497 $ 34,882 $ 24,236 $ 11 $ 8,344,626 As of December 31, 2017 Pass Special Substandard Doubtful Total Residential real estate $ 2,593,096 $ 309 $ 171 $ — $ 2,593,576 Commercial and industrial 2,385,152 22,443 30,343 — 2,437,938 Securities-based loans 1,819,206 — — — 1,819,206 Commercial real estate 116,258 — — — 116,258 Home equity lines of credit 14,855 — 184 — 15,039 Construction and land 7,896 — — — 7,896 Other 24,506 — 2 — 24,508 Total $ 6,960,969 $ 22,752 $ 30,700 $ — $ 7,014,421

Goodwill And Intangible Assets

Goodwill And Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Carrying Amount Of Goodwill And Intangible Assets	The carrying amount of goodwill and intangible assets attributable to each of our reporting segments is presented in the following table (in thousands) December 31, 2017 Adjustments Write-off September 30, 2018 Goodwill Global Wealth Management $ 276,477 $ 54,969 $ — $ 331,446 Institutional Group 692,357 1,911 — 694,268 $ 968,834 $ 56,880 $ — $ 1,025,714 December 31, 2017 Net Additions Amortization September 30, 2018 Intangible assets Global Wealth Management $ 44,525 $ 17,180 $ (3,662 ) $ 58,043 Institutional Group 65,102 857 (5,079 ) 60,880 $ 109,627 $ 18,037 $ (8,741 ) $ 118,923
Intangible Assets Subject To Amortization	Intangible assets subject to amortization as of September 30, 2018 and December 31, 2017 were as follows (in thousands) September 30, 2018 December 31, 2017 Gross Carrying Value Accumulated Amortization Gross Carrying Value Accumulated Amortization Customer relationships $ 156,240 $ 62,822 $ 146,986 $ 55,809 Trade name 24,713 11,373 24,713 10,228 Non-compete agreements 2,603 1,388 2,598 1,202 Investment banking backlog 1,431 1,214 1,419 968 Estimated BBI intangibles (1) 8,615 — — — $ 193,602 $ 76,797 $ 175,716 $ 68,207 (1)
Amortization Expense In Future Periods	As of September 30, 2018, we expect amortization expense in future periods to be as follows (in thousands) Fiscal year Remainder of 2018 $ 3,382 2019 12,974 2020 12,757 2021 12,258 2022 11,798 Thereafter 63,636 $ 116,805

Senior Notes (Tables)

Senior Notes (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Summary of Senior Notes	The following table summarizes our senior notes as of September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 December 31, 2017 4.250% senior notes, due 2024 (1) $ 500,000 $ 500,000 3.50% senior notes, due 2020 (2) 300,000 300,000 5.20% senior notes, due 2047 (3) 225,000 225,000 1,025,000 1,025,000 Debt issuance costs, net (9,286 ) (10,060 ) $ 1,015,714 $ 1,014,940 (1) In July 2014, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 4.250% senior notes due July 2024. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption. In July 2016, we issued an additional $200.0 million in aggregate principal amount of 4.25% senior notes due 2024. (2) In December 2015, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 3.50% senior notes due December 2020. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption. (3)
Schedule of Corporate Date Maturity	Our senior notes mature as follows, based upon contractual terms (in thousands) 2018 $ — 2019 — 2020 300,000 2021 — 2022 — Thereafter 725,000 $ 1,025,000

Bank Deposits (Tables)

Bank Deposits (Tables)	9 Months Ended
	Sep. 30, 2018
Deposits Liabilities Balance Sheet Reported Amounts [Abstract]
Schedule Of Deposits	Deposits consist of money market and savings accounts, certificates of deposit, and demand deposits. Deposits at September 30, 2018 and December 31, 2017 were as follows (in thousands) September 30, 2018 December 31, 2017 Money market and savings accounts $ 11,950,269 $ 13,219,675 Certificates of deposit 1,970,318 1,575 Demand deposits (interest-bearing) 465,366 184,829 Demand deposits (non-interest-bearing) 116,999 5,856 $ 14,502,952 $ 13,411,935
Schedule of Maturities of Certificates of Deposit	Scheduled maturities of certificates of deposit at September 30, 2018 and December 31, 2017 were as follows (in thousands): September 30, 2018 December 31, 2017 Certificates of deposit, less than $100: Within one year $ 5,617 $ 438 One to three years 544 148 Three to five years 127 — $ 6,288 $ 586 Certificates of deposit, $100 and greater: Within one year $ 1,740,855 $ 651 One to three years 193,185 338 Three to five years 29,990 — 1,964,030 989 $ 1,970,318 $ 1,575

Derivative Instruments And He_2

Derivative Instruments And Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2018
General Discussion Of Derivative Instruments And Hedging Activities [Abstract]
Schedule Of Notional Values And Fair Values Of Derivative Instruments	The following table provides the notional values and fair values of our derivative instruments as of September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 Notional Balance Location Fair Value Asset Derivatives Cash flow interest rate contracts $ 540,000 Other assets $ 11,117 December 31, 2017 Notional Value Balance Location Fair Value Asset Derivatives Cash flow interest rate contracts $ 540,000 Other assets $ 7,995
Schedule Of Derivative Instruments In Consolidated Statements Of Operations	The following table shows the effect of our company’s derivative instruments in the consolidated statements of operations for the three and nine months ended September 30, 2018 and 2017 (in thousands) Three Months Ended September 30, 2018 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Gain/(Loss) Recognized Due to Ineffectiveness Cash flow interest rate contracts $ (603 ) Interest expense $ 1,504 Interest expense $ — Three Months Ended September 30, 2017 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Gain/(Loss) Recognized Due to Ineffectiveness Cash flow interest rate contracts $ 928 Interest $ 724 Interest expense $ — Nine Months Ended September 30, 2018 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Loss Recognized Due to Ineffectiveness Cash flow interest rate contracts $ (5,823 ) Interest $ 3,262 Interest expense $ — Nine Months Ended September 30, 2017 Gain/(Loss) Recognized in OCI (Effectiveness) Location of Loss Reclassified From OCI Into Income Gain/(Loss) Reclassified From OCI Into Income Location of Loss Recognized in OCI (Ineffectiveness) Loss Recognized Due to Ineffectiveness Cash flow interest rate contracts $ 3,504 Interest expense $ (810 ) Interest expense $ —

Disclosures About Offsetting _2

Disclosures About Offsetting Assets And Liabilities (Tables)	9 Months Ended
	Sep. 30, 2018
Offsetting [Abstract]
Financial Assets And Derivative Assets That Are Subject to Offset	The following table provides information about financial assets and derivative assets that are subject to offset as of September 30, 2018 and December 31, 2017 (in thousands) Gross amounts not offset in the Statement of Financial Condition Gross Amounts of Recognized Assets Gross Amounts Offset in the Statement of Financial Condition Net Amounts Presented in the of Financial Condition Amounts available for offset Available collateral Net Amount As of September 30, 2018: Securities borrowing (1) $ 170,165 $ — $ 170,165 $ (47,974 ) $ (110,088 ) $ 12,103 Reverse repurchase agreements (2) 622,361 — 622,361 (261,773 ) (356,842 ) 3,746 Cash flow interest rate contracts 11,117 — 11,117 — — 11,117 $ 803,643 $ — $ 803,643 $ (309,747 ) $ (466,930 ) $ 26,966 As of December 31, 2017: Securities borrowing (1) $ 132,776 $ — $ 132,776 $ (78,474 ) $ (37,248 ) $ 17,054 Reverse repurchase agreements (2) 512,220 — 512,220 (233,624 ) (266,008 ) 12,588 Cash flow interest rate contracts 7,995 — 7,995 — — 7,995 $ 652,991 $ — $ 652,991 $ (312,098 ) $ (303,256 ) $ 37,637 (1) Securities borrowing transactions are included in receivables from brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on receivables from brokers, dealers, and clearing organizations. (2) Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.
Financial Liabilities And Derivative Liabilities That Are Subject To Offset	The following table provides information about financial liabilities and derivative liabilities that are subject to offset as of September 30, 2018 and December 31, 2017 (in thousands) Gross amounts not offset in the Statement of Financial Condition Gross Amounts of Recognized Liabilities Gross Amounts Offset in the of Financial Condition Net Amounts Presented in the Statement of Financial Condition Amounts available for offset Collateral Pledged Net Amount As of September 30, 2018: Securities lending (3) $ (691,150 ) $ — $ (691,150 ) $ 47,974 $ 616,157 $ (27,019 ) Repurchase agreements (4) (495,484 ) — (495,484 ) 261,773 233,711 — $ (1,186,634 ) $ — $ (1,186,634 ) $ 309,747 $ 849,868 $ (27,019 ) As of December 31, 2017: Securities lending (3) $ (219,782 ) $ — $ (219,782 ) $ 78,474 $ 133,772 $ (7,536 ) Repurchase agreements (4) (233,704 ) — (233,704 ) 233,624 80 — $ (453,486 ) $ — $ (453,486 ) $ 312,098 $ 133,852 $ (7,536 ) (3) Securities lending transactions are included in payables to brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on payables to brokers, dealers, and clearing organizations. (4) Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Regulatory Capital Requiremen_2

Regulatory Capital Requirements (Tables)	9 Months Ended
	Sep. 30, 2018
Regulatory Capital Requirements [Abstract]
Schedule Of Total Risk-Based, Tier 1 Risk-Based, And Tier 1 Leverage Ratios	Stifel Financial Corp. – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 1,931,840 16.7 % $ 521,580 4.5 % $ 753,393 6.5 % Tier 1 capital 2,081,840 18.0 % 695,439 6.0 % 927,252 8.0 % Total capital 2,232,951 19.3 % 927,252 8.0 % 1,159,066 10.0 % Tier 1 leverage 2,081,840 9.6 % 864,465 4.0 % 1,080,581 5.0 % Stifel Bank & Trust – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 1,142,936 14.2 % $ 361,454 4.5 % $ 522,100 6.5 % Tier 1 capital 1,142,936 14.2 % 481,939 6.0 % 642,585 8.0 % Total capital 1,223,636 15.2 % 642,585 8.0 % 803,231 10.0 % Tier 1 leverage 1,142,936 7.0 % 651,837 4.0 % 814,797 5.0 % Stifel Bank – Federal Reserve Capital Amounts September 30, 2018 Actual For Capital Adequacy Purposes To Be Well Capitalized Under Prompt Corrective Action Provisions Amount Ratio Amount Ratio Amount Ratio Common equity tier 1 capital $ 75,385 13.8 % $ 24,666 4.5 % $ 35,629 6.5 % Tier 1 capital 75,385 13.8 % 32,888 6.0 % 43,851 8.0 % Total capital 82,246 15.0 % 43,851 8.0 % 54,814 10.0 % Tier 1 leverage 75,385 12.5 % 24,137 4.0 % 30,171 5.0 %

Revenues from Contracts with _2

Revenues from Contracts with Customers (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue From Contract With Customer [Abstract]
Schedule of Total Revenues Separated between Revenues from Contracts with Customers and Other Sources of Revenues	The following table presents the Company’s total revenues separated between revenues from contracts with customers and other sources of revenues for the three and nine months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 Nine Months Ended September 30, 2018 Revenues from contracts with customers: Commissions $ 158,016 $ 490,693 Investment banking 169,012 506,437 Asset management and service fees 200,743 596,112 Other 4,394 11,908 Total revenue from contracts with customers 532,165 1,605,150 Other sources of revenue: Interest 169,760 461,915 Principal transactions 83,152 269,918 Other 1,733 6,649 Total revenues $ 786,810 $ 2,343,632
Revenues from Contracts with Customers Disaggregated by Major Business Activity and Primary Geographic Regions	The following tables present the Company’s revenues from contracts with customers by reportable segment disaggregated by major business activity and primary geographic regions for the three and nine months ended September 30, 2018 (in thousands) Three Months Ended September 30, 2018 (1) Global Wealth Management Institutional Group Total Major business activity: Commissions $ 117,795 $ 40,220 $ 158,015 Investment banking - capital raising 7,722 85,553 93,275 Investment banking - advisory fees — 75,717 75,717 Asset management 200,735 8 200,743 Other 4,394 — 4,394 Total 330,646 201,498 532,144 Primary Geographic Region: United States 330,646 172,382 503,028 Europe — 28,197 28,197 Other — 919 919 $ 330,646 $ 201,498 $ 532,144 Nine Months Ended September 30, 2018 (1) Global Wealth Management Institutional Group Total Major business activity: Commissions $ 355,129 $ 135,563 $ 490,692 Investment banking - capital raising 23,378 222,666 246,044 Investment banking - advisory fees 81 260,312 260,393 Asset management 596,081 31 596,112 Other 11,908 — 11,908 Total 986,577 618,572 1,605,149 Primary Geographic Region: United States 986,577 522,147 1,508,724 Europe — 92,029 92,029 Other — 4,396 4,396 $ 986,577 $ 618,572 $ 1,605,149 (1)

Interest Income And Interest _2

Interest Income And Interest Expense (Tables)	9 Months Ended
	Sep. 30, 2018
Banking And Thrift Interest [Abstract]
Components Of Interest Income And Interest Expense	The components of interest income and interest expense are as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Interest income: Bank loans, net $ 78,766 $ 54,006 $ 210,790 $ 147,495 Investment securities 66,825 48,072 185,263 136,123 Margin balances 13,066 9,919 36,322 27,124 Financial instruments owned 5,733 4,371 15,645 12,953 Other 5,370 1,494 13,895 4,071 $ 169,760 $ 117,862 $ 461,915 $ 327,766 Interest expense: Bank deposits $ 25,856 $ 4,770 $ 49,329 $ 8,424 Senior notes 11,248 8,655 33,488 24,935 Federal Home Loan Bank advances 4,232 1,255 10,579 5,771 Other 7,132 2,945 18,804 11,035 $ 48,468 $ 17,625 $ 112,200 $ 50,165

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Schedule Of Operating Information, Segment	Information concerning operations in these segments of business for the three and nine months ended September 30, 2018 and 2017 is as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net revenues: (1) Global Wealth Management $ 498,161 $ 453,558 $ 1,481,063 $ 1,348,280 Institutional Group 245,952 264,747 768,855 778,367 Other (5,771 ) 2,864 (18,486 ) (4,300 ) $ 738,342 $ 721,169 $ 2,231,432 $ 2,122,347 Income/(loss) before income taxes: Global Wealth Management $ 183,377 $ 161,756 $ 548,043 $ 457,045 Institutional Group 34,305 51,717 114,899 144,481 Other (77,152 ) (105,334 ) (284,511 ) (331,170 ) $ 140,530 $ 108,139 $ 378,431 $ 270,356 (1) No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2018 or 2017.
Schedule Of Information Of Total Assets On Segment Basis	The following table presents our company’s total assets on a segment basis at September 30, 2018 and December 31, 2017 (in thousands) September 30, 2018 December 31, 2017 Global Wealth Management $ 19,874,154 $ 17,717,617 Institutional Group 3,511,720 3,313,304 Other 374,174 353,032 $ 23,760,048 $ 21,383,953
Schedule Of Net Revenues Earned On Major Geographical Areas	Revenues, classified by the major geographic areas in which they are earned for the three and nine months ended September 30, 2018 and 2017, were as follows (in thousands) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 United States $ 703,746 $ 680,505 $ 2,113,039 $ 2,017,999 United Kingdom 32,623 38,103 109,482 95,393 Other 1,973 2,561 8,911 8,955 $ 738,342 $ 721,169 $ 2,231,432 $ 2,122,347

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2018
Earnings Per Share [Abstract]
Computation Of Basic And Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted earnings per share for the three and nine months ended September 30, 2018 and 2017 (in thousands, except per share data) Three Months Ended September 30, Nine Months Ended September 30, 2018 2017 2018 2017 Net income $ 103,858 $ 66,536 $ 279,906 $ 184,859 Preferred dividends 2,343 2,343 7,031 7,031 Net income available to common shareholders $ 101,515 $ 64,193 $ 272,875 $ 177,828 Shares for basic and diluted calculation: Average shares used in basic computation 71,919 68,522 71,824 68,488 Dilutive effect of stock options and units (1) 9,565 12,359 9,601 12,074 Average shares used in diluted computation 81,484 80,881 81,425 80,562 Earnings per common share: Basic $ 1.41 $ 0.94 $ 3.80 $ 2.60 Diluted $ 1.25 $ 0.79 $ 3.35 $ 2.21 (1) Diluted earnings per share is computed on the basis of the weighted-average number of shares of common stock plus the effect of dilutive potential common shares outstanding during the period using the treasury stock method.

Nature of Operations and Basi_3

Nature of Operations and Basis of Presentation (Narrative) (Details) shares in Millions, $ in Millions	Aug. 31, 2018USD ($)shares	Mar. 19, 2018USD ($)ClientAdvisorState
Ziegler [Member]
Nature Of Operations Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Date of acquisition		Mar. 19, 2018
Number of private client advisors | ClientAdvisor		55
Number of states in which private client advisors operates | State		5
Assets		$ 5,000
Business Bancshares, Inc. [Member]
Nature Of Operations Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Date of acquisition	Aug. 31, 2018
Assets	$ 600
Shares issued for acquisition | shares	2

New Accounting Pronouncements_2

New Accounting Pronouncements (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Other operating expenses	$ 76,785	$ 61,311	$ 231,122	$ 209,581
ASU 2018-02 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Reclassification adjustment related to cash flow hedges and investment portfolio credit risk			3,000
ASU 2016-18 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Decrease in net cash provided by operating activities				$ 48,100
ASU 2014-09 [Member]
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Cumulative effect on retained earnings			3,900
Capital raising and advisory fee revenues	$ 25,900		25,900
Other operating expenses			$ 25,900

Receivables From And Payables_3

Receivables From And Payables To Brokers, Dealers And Clearing Organizations (Amounts Receivable From Brokers, Dealers, And Clearing Organizations) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Due To And From Broker Dealers And Clearing Organizations [Abstract]
Receivables from clearing organizations	$ 440,154	$ 270,285
Deposits paid for securities borrowed	170,165	132,776
Securities failed to deliver	35,801	56,046
Receivables from brokers, dealers and clearing organizations, Total	$ 646,120	$ 459,107

Receivables From And Payables_4

Receivables From And Payables To Brokers, Dealers And Clearing Organizations (Amounts Payable To Brokers, Dealers, And Clearing Organizations) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Due To And From Broker Dealers And Clearing Organizations [Abstract]
Deposits received from securities loaned	$ 691,150	$ 219,782
Payable to clearing organizations	201,510	27,223
Securities failed to receive	35,472	29,297
Payables to broker, dealers and clearing organizations, Total	$ 928,132	$ 276,302

Fair Value Of Financial Instrum

Fair Value Of Financial Instruments (Schedule Of Fair Value Of Investments In And Unfunded Commitments To Funds Measured At Net Asset Value) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fair value of investments	$ 37,001	$ 101,990
Unfunded commitments	2,859	3,155
Partnership Interests [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fair value of investments	4,405	5,124
Unfunded commitments	1,324	1,330
Mutual Funds [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fair value of investments	10,506	11,748
Private Equity Funds [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fair value of investments	3,394	7,677
Unfunded commitments	1,535	1,825
Money Market Funds [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fair value of investments	$ 18,696	$ 77,441

Fair Value Of Financial Instr_2

Fair Value Of Financial Instruments (Fair Value Of Assets And Liabilities Measured On Recurring Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	$ 1,162,732	$ 1,143,684
Available-for-sale securities	3,349,607	3,773,508
Investments	79,170	111,379
Cash equivalents measured at NAV	18,696	77,441
Derivative contracts, Assets	11,117	7,995
Total Assets	4,621,322	5,114,007
Financial instruments sold, but not yet purchased, at fair value	911,374	778,863
Sovereign Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	15,996	32,470
Financial instruments sold, but not yet purchased, at fair value	11,557	20,236
U.S. Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	167,886	147,223
Available-for-sale securities	5,165	4,983
Financial instruments sold, but not yet purchased, at fair value		10,348
Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	29,806	76,752
Available-for-sale securities	1,777,351	2,106,938
Corporate Fixed Income Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	290,627	325,471
Available-for-sale securities	1,177,315	1,211,442
Financial instruments sold, but not yet purchased, at fair value	213,335	180,755
Corporate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	69,205	46,802
Investments	42,495	49,978
Financial instruments sold, but not yet purchased, at fair value	78,895	38,510
State And Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	149,207	169,699
Available-for-sale securities	68,876	70,559
Auction Rate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	16,525	34,789
Auction Rate Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	799	846
Other Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,046	1,217
Investments In Funds Measured At NAV [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	18,305	24,549
U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	36,214	13,466
Financial instruments sold, but not yet purchased, at fair value	512,275	442,402
Mortgage Backed Securities [Member] | Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	380,044	302,445
Available-for-sale securities	250,808	305,530
Financial instruments sold, but not yet purchased, at fair value	95,312	86,612
Mortgage Backed Securities [Member] | Non-Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	23,747	29,356
Available-for-sale securities	1,269	1,568
Mortgage Backed Securities [Member] | Commercial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	68,823	72,488
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	105,368	60,239
Available-for-sale securities	516	516
Investments	42,495	49,978
Total Assets	148,379	110,733
Financial instruments sold, but not yet purchased, at fair value	591,266	480,472
Level 1 [Member] | U.S. Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	516	516
Level 1 [Member] | Corporate Fixed Income Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	262	362
Financial instruments sold, but not yet purchased, at fair value	96
Level 1 [Member] | Corporate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	68,892	46,411
Investments	42,495	49,978
Financial instruments sold, but not yet purchased, at fair value	78,895	38,070
Level 1 [Member] | U.S. Government Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	36,214	13,466
Financial instruments sold, but not yet purchased, at fair value	512,275	442,402
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	1,056,907	1,082,592
Available-for-sale securities	3,349,091	3,772,992
Investments	189	360
Derivative contracts, Assets	11,117	7,995
Total Assets	4,417,304	4,863,939
Financial instruments sold, but not yet purchased, at fair value	320,108	298,391
Level 2 [Member] | Sovereign Debt [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	15,996	32,470
Financial instruments sold, but not yet purchased, at fair value	11,557	20,236
Level 2 [Member] | U.S. Government Agency Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	167,886	147,223
Available-for-sale securities	4,649	4,467
Financial instruments sold, but not yet purchased, at fair value		10,348
Level 2 [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	29,451	76,395
Available-for-sale securities	1,777,351	2,106,938
Level 2 [Member] | Corporate Fixed Income Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	290,365	324,867
Available-for-sale securities	1,177,315	1,211,442
Financial instruments sold, but not yet purchased, at fair value	213,239	180,755
Level 2 [Member] | Corporate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	212	138
Financial instruments sold, but not yet purchased, at fair value		440
Level 2 [Member] | State And Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	149,207	169,699
Available-for-sale securities	68,876	70,559
Level 2 [Member] | Other Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	189	360
Level 2 [Member] | Mortgage Backed Securities [Member] | Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	380,044	302,445
Available-for-sale securities	250,808	305,530
Financial instruments sold, but not yet purchased, at fair value	95,312	86,612
Level 2 [Member] | Mortgage Backed Securities [Member] | Non-Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	23,746	29,355
Available-for-sale securities	1,269	1,568
Level 2 [Member] | Mortgage Backed Securities [Member] | Commercial [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	68,823	72,488
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	457	853
Investments	18,181	36,492
Total Assets	18,638	37,345
Level 3 [Member] | Asset-Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	355	357
Level 3 [Member] | Corporate Fixed Income Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned		242
Level 3 [Member] | Corporate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	101	253
Level 3 [Member] | Auction Rate Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	16,525	34,789
Level 3 [Member] | Auction Rate Municipal Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	799	846
Level 3 [Member] | Other Investment [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	857	857
Level 3 [Member] | Mortgage Backed Securities [Member] | Non-Agency [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial instruments owned	$ 1	$ 1

Fair Value Of Financial Instr_3

Fair Value Of Financial Instruments (Schedule Of Changes In Fair Value Associated With Level 3 Financial Instruments) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Transfers, Into Level 3		$ 0
Transfers, Out of Level 3		0
Non-Agency [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	$ 1	1
Ending Balance	1	1
Asset-Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	355	357
Unrealized gains/(losses), Included in changes in net assets		3
Redemptions		(5)
Net change		(2)
Ending Balance	355	355
Equity Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	123	253
Unrealized gains/(losses), Included in changes in net assets		(130)
Realized gains/(losses)	(22)	(22)
Net change	(22)	(152)
Ending Balance	101	101
Equity Auction Rate Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	25,303	34,789
Unrealized gains/(losses), Included in changes in net assets	997	1,086
Redemptions	(9,775)	(19,350)
Net change	(8,778)	(18,264)
Ending Balance	16,525	16,525
Auction Rate Municipal Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	846	846
Unrealized gains/(losses), Included in changes in net assets	3	3
Redemptions	(50)	(50)
Net change	(47)	(47)
Ending Balance	799	799
Other Investment [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance	857	857
Ending Balance	$ 857	857
Fixed Income Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		242
Redemptions		(242)
Net change		$ (242)

Fair Value Of Financial Instr_4

Fair Value Of Financial Instruments (Quantitative Information related To The Significant Unobservable Inputs Utilized In Company's Level 3 Recurring Fair Value Measurements) (Details) - Discounted Cash Flow [Member]	9 Months Ended
	Sep. 30, 2018
Auction Rate Equity Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Workout period range, low end	2 years
Workout period range, high end	3 years
Discount rate, weighted average	3.80%
Weighted average workout period	2 years 4 months 24 days
Auction Rate Equity Securities [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range	0.60%
Auction Rate Equity Securities [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range	6.50%
Auction Rate Municipal Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Workout period range, low end	1 year
Workout period range, high end	4 years
Discount rate, weighted average	3.20%
Weighted average workout period	2 years
Auction Rate Municipal Securities [Member] | Minimum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range	0.50%
Auction Rate Municipal Securities [Member] | Maximum [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Discount rate range	9.90%

Fair Value Of Financial Instr_5

Fair Value Of Financial Instruments (Narrative) (Details) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2018USD ($)
Fair Value Disclosures [Abstract]
Transfers of financial assets from Level 2 to Level 1	$ 0	$ 0.6
Transfers of financial assets from Level 1 to Level 2	$ 0.1	0.7
Transfers of financial assets into Level 3		0
Transfers of financial assets out of Level 3		$ 0
Stated interest rate	4.25%	4.25%
Maturity date		Dec. 31, 2024

Fair Value Of Financial Instr_6

Fair Value Of Financial Instruments (Schedule Of Fair Value Of Financial Instruments) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities purchased under agreements to resell	[1]	$ 622,361	$ 512,220
Financial instruments owned		1,162,732	1,143,684
Available-for-sale securities		3,349,607	3,773,508
Held-to-maturity securities	[2]	4,506,385	3,710,478
Investments, at fair value		79,170	111,379
Derivative contracts		11,117	7,995
Securities sold under agreements to repurchase	[3]	495,484	233,704
Bank deposits		14,502,952	13,411,935
Financial instruments sold, but not yet purchased, at fair value		911,374	778,863
Borrowings		140,030	256,000
Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		694,302	696,283
Cash segregated for regulatory purposes		21,585	90,802
Securities purchased under agreements to resell		622,361	512,220
Financial instruments owned		1,162,732	1,143,684
Available-for-sale securities		3,349,607	3,773,508
Held-to-maturity securities		4,565,453	3,698,098
Loans held for sale		262,063	226,068
Bank loans		8,253,989	6,947,759
Investments, at fair value		79,170	111,379
Derivative contracts	[4]	11,117	7,995
Securities sold under agreements to repurchase		495,484	233,704
Bank deposits		14,502,952	13,411,935
Financial instruments sold, but not yet purchased, at fair value		911,374	778,863
Federal Home Loan Bank advances		1,064,000	745,000
Borrowings		140,030	256,000
Senior notes		1,015,714	1,014,940
Debentures to Stifel Financial Capital Trusts		67,500	67,500
Estimated Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and cash equivalents		694,302	696,283
Cash segregated for regulatory purposes		21,585	90,802
Securities purchased under agreements to resell		622,361	512,220
Financial instruments owned		1,162,732	1,143,684
Available-for-sale securities		3,349,607	3,773,508
Held-to-maturity securities		4,506,385	3,710,478
Loans held for sale		262,063	226,068
Bank loans		8,330,974	6,953,328
Investments, at fair value		79,170	111,379
Derivative contracts	[4]	11,117	7,995
Securities sold under agreements to repurchase		495,484	233,704
Bank deposits		13,711,447	12,702,746
Financial instruments sold, but not yet purchased, at fair value		911,374	778,863
Federal Home Loan Bank advances		1,064,000	745,000
Borrowings		140,030	256,000
Senior notes		1,012,374	1,044,768
Debentures to Stifel Financial Capital Trusts		$ 68,839	$ 64,962
[1]	Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.
[3]	Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.
[4]	Included in other assets in the consolidated statements of financial condition

Fair Value Of Financial Instr_7

Fair Value Of Financial Instruments (Estimated Fair Values Of Financial Instruments Not Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell	[1]	$ 622,361	$ 512,220
Held-to-maturity securities	[2]	4,506,385	3,710,478
Securities sold under agreements to repurchase	[3]	495,484	233,704
Bank deposits		14,502,952	13,411,935
Borrowings		140,030	256,000
Senior notes		1,015,714	1,014,940
Fair Value, Measurements, Nonrecurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		675,606	618,842
Cash segregated for regulatory purposes		21,585	90,802
Securities purchased under agreements to resell		622,361	512,220
Held-to-maturity securities		4,506,385	3,710,478
Loans held for sale		262,063	226,068
Bank loans		8,330,974	6,953,328
Securities sold under agreements to repurchase		495,484	233,704
Bank deposits		13,711,447	12,702,746
Federal Home Loan Bank advances		1,064,000	745,000
Borrowings		140,030	256,000
Senior notes		1,012,374	1,044,768
Debentures to Stifel Financial Capital Trusts		68,839	64,962
Fair Value, Measurements, Nonrecurring [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash		675,606	618,842
Cash segregated for regulatory purposes		21,585	90,802
Securities purchased under agreements to resell		586,829	428,740
Securities sold under agreements to repurchase		126,378	92,278
Federal Home Loan Bank advances		1,064,000	745,000
Borrowings		140,030	256,000
Senior notes		1,012,374	1,044,768
Fair Value, Measurements, Nonrecurring [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Securities purchased under agreements to resell		35,532	83,480
Held-to-maturity securities		4,345,021	3,517,781
Loans held for sale		262,063	226,068
Bank loans		8,330,974	6,953,328
Securities sold under agreements to repurchase		369,106	141,426
Bank deposits		13,711,447	12,702,746
Fair Value, Measurements, Nonrecurring [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity securities		161,364	192,697
Debentures to Stifel Financial Capital Trusts		$ 68,839	$ 64,962
[1]	Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.
[3]	Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Financial Instruments Owned A_3

Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased (Components Of Trading Securities Owned And Trading Securities Sold, But Not Yet Purchased) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	$ 1,162,732	$ 1,143,684
U.S. Government Agency Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	167,886	147,223
Corporate Fixed Income Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	290,627	325,471
Corporate Equity Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	69,205	46,802
State and Municipal Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	149,207	169,699
U.S. Government Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	36,214	13,466
Sovereign Debt [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	15,996	32,470
Securities Sold, But Not yet Purchased [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments owned, at fair value	911,374	778,863
Securities Sold, But Not yet Purchased [Member] | U.S. Government Agency Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned		10,348
Securities Sold, But Not yet Purchased [Member] | Corporate Fixed Income Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Fixed income securities	213,335	180,755
Securities Sold, But Not yet Purchased [Member] | Corporate Equity Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Equity securities	78,895	38,510
Securities Sold, But Not yet Purchased [Member] | U.S. Government Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	512,275	442,402
Securities Sold, But Not yet Purchased [Member] | Mortgage Backed Securities [Member] | Agency [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	95,312	86,612
Securities Sold, But Not yet Purchased [Member] | Sovereign Debt [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Sovereign debt	11,557	20,236
Securities Owned
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Asset-backed securities	29,806	76,752
Financial instruments owned, at fair value	1,162,732	1,143,684
Securities Owned | U.S. Government Agency Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	167,886	147,223
Securities Owned | Corporate Fixed Income Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Fixed income securities	290,627	325,471
Securities Owned | Corporate Equity Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Equity securities	69,205	46,802
Securities Owned | State and Municipal Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
State and municipal securities	149,207	169,699
Securities Owned | U.S. Government Securities [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	36,214	13,466
Securities Owned | Mortgage Backed Securities [Member] | Agency [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	380,044	302,445
Securities Owned | Mortgage Backed Securities [Member] | Non-Agency [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Trading securities owned	23,747	29,356
Securities Owned | Sovereign Debt [Member]
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Sovereign debt	$ 15,996	$ 32,470

Financial Instruments Owned A_4

Financial Instruments Owned And Financial Instruments Sold, But Not Yet Purchased (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments pledged as collateral	$ 2,000	$ 2,200
Securities Owned
Schedule Of Trading Securities And Other Trading Assets [Line Items]
Financial instruments pledged as collateral	$ 534.6	$ 810.3

Available-For-Sale And Held-T_3

Available-For-Sale And Held-To-Maturity Securities (Schedule Of Amortized Cost And Fair Values Of The Available For Sale Securities And Held To Maturity Securities) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		$ 3,393,128	$ 3,777,458
Available for sale securities, unrealized gains	[1]	5,688	16,839
Available-for-sale Securities, Gross unrealized losses	[1]	(49,209)	(20,789)
Available-for-sale securities		3,349,607	3,773,508
Held-to-maturity Securities, Amortized cost	[2]	4,565,453	3,698,098
Held-to-maturity Securities, Gross unrealized gains	[2]	4,940	30,487
Held-to-maturity Securities, Gross unrealized losses	[2]	(64,008)	(18,107)
Held-to-maturity securities, Estimated fair value	[2]	4,506,385	3,710,478
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		5,226	5,022
Available-for-sale Securities, Gross unrealized losses	[1]	(61)	(39)
Available-for-sale securities		5,165	4,983
State And Municipal Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		73,253	74,691
Available-for-sale Securities, Gross unrealized losses	[1]	(4,377)	(4,132)
Available-for-sale securities		68,876	70,559
Mortgage Backed Securities [Member] | Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		256,120	308,409
Available for sale securities, unrealized gains	[1]	29	102
Available-for-sale Securities, Gross unrealized losses	[1]	(5,341)	(2,981)
Available-for-sale securities		250,808	305,530
Held-to-maturity Securities, Amortized cost	[2]	1,244,582	1,334,833
Held-to-maturity Securities, Gross unrealized gains	[2]		13,621
Held-to-maturity Securities, Gross unrealized losses	[2]	(48,907)	(16,208)
Held-to-maturity securities, Estimated fair value	[2]	1,195,675	1,332,246
Mortgage Backed Securities [Member] | Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		74,698	75,548
Available for sale securities, unrealized gains	[1]	8	28
Available-for-sale Securities, Gross unrealized losses	[1]	(5,883)	(3,088)
Available-for-sale securities		68,823	72,488
Held-to-maturity Securities, Amortized cost	[2]	55,351	58,971
Held-to-maturity Securities, Gross unrealized gains	[2]		1,313
Held-to-maturity Securities, Gross unrealized losses	[2]	(343)
Held-to-maturity securities, Estimated fair value	[2]	55,008	60,284
Mortgage Backed Securities [Member] | Non-Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		1,281	1,568
Available-for-sale Securities, Gross unrealized losses	[1]	(12)
Available-for-sale securities		1,269	1,568
Corporate Fixed Income Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		1,200,498	1,213,262
Available for sale securities, unrealized gains	[1]	2,542	3,832
Available-for-sale Securities, Gross unrealized losses	[1]	(25,725)	(5,652)
Available-for-sale securities		1,177,315	1,211,442
Held-to-maturity Securities, Amortized cost	[2]		40,011
Held-to-maturity Securities, Gross unrealized gains	[2]		27
Held-to-maturity Securities, Gross unrealized losses	[2]		(37)
Held-to-maturity securities, Estimated fair value	[2]		40,001
Asset-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Amortized cost		1,782,052	2,098,958
Available for sale securities, unrealized gains	[1]	3,109	12,877
Available-for-sale Securities, Gross unrealized losses	[1]	(7,810)	(4,897)
Available-for-sale securities		1,777,351	2,106,938
Held-to-maturity Securities, Amortized cost	[2]	3,265,520	2,264,283
Held-to-maturity Securities, Gross unrealized gains	[2]	4,940	15,526
Held-to-maturity Securities, Gross unrealized losses	[2]	(14,758)	(1,862)
Held-to-maturity securities, Estimated fair value	[2]	$ 3,255,702	$ 2,277,947
[1]	Unrealized gains/(losses) related to available-for-sale securities are reported in accumulated other comprehensive loss.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.

Available-For-Sale And Held-T_4

Available-For-Sale And Held-To-Maturity Securities (Narrative) (Details) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018USD ($)security	Sep. 30, 2017USD ($)	Sep. 30, 2018USD ($)security	Sep. 30, 2017USD ($)	Dec. 31, 2017USD ($)
Other Than Temporary Impairment Credit Losses Recognized In Earnings [Line Items]
Proceeds from sale of available-for-sale securities		$ 55,400	$ 0	$ 55,400	$ 87,300
Net realized gains (loss) resulting from sale of available-for-sale securities		(400)		(400)	400
Unrealized gains (losses) recorded in accumulated other comprehensive loss	[1],[2],[3]	(3,138)	4,736	(28,065)	12,283
Financial instruments pledged as collateral		$ 2,000,000		$ 2,000,000		$ 2,200,000
Number of available for sale securities whose amortized costs exceeded their fair values | security		232		232
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Losses		$ 49,209		$ 49,209
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses		26,542		26,542
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value		$ 1,764,637		$ 1,764,637
Percentage of available-for-sale portfolio		52.70%		52.70%
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions | security		152		152
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss		$ 64,008		$ 64,008
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss		39,563		39,563
Credit-related OTTI		0	$ 0	0	$ 0
Gross unrealized losses related to investment portfolio				113,200
Pledged [Member]
Other Than Temporary Impairment Credit Losses Recognized In Earnings [Line Items]
Trading securities pledged		$ 2,100,000		$ 2,100,000		$ 2,000,000
[1]	Net of tax benefit of $2.1 million and tax expense of $5.0 million for the three months ended September 30, 2018 and 2017, respectively. Net of tax benefit of $10.4 million and tax expense of $13.5 million for the nine months ended September 30, 2018 and 2017, respectively.
[2]	The adoption of ASU 2018-02 on January 1, 2018 resulted in a reclassification of $3.0 million to retained earnings related to cash flow hedges and investment portfolio risk. The reclassification is reflected in the activity for the nine months ended September 30, 2018. See Note 2 for further details.
[3]	There were no reclassifications to earnings during the three and nine months ended September 30, 2018 and 2017, respectively.

Available-For-Sale And Held-T_5

Available-For-Sale And Held-To-Maturity Securities (Schedule Of Amortized Cost And Fair Values Of Debt Securities By Contractual Maturity) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Schedule Of Debt Securities At Amortized Cost And Fair Value Basis [Line Items]
Available-for-sale Securities, debt maturities, Amortized Cost		$ 3,393,128
Available-for-sale Securities, debt maturities, within one year, Fair Value	[1]	37,275
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	696,128
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	1,896,648
Available-for-sale Securities, debt maturities, Fair Value	[1]	3,349,607
Held-to-maturity Securities, debt maturities, after five through ten years, Amortized Cost		658,457
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		3,851,645
Held-to-maturity Securities, Amortized cost	[2]	4,565,453	$ 3,698,098
Held-to-maturity Securities, debt maturities, Fair Value	[2]	4,506,385	$ 3,710,478
Excluding Mortgage Backed Securities [Member]
Schedule Of Debt Securities At Amortized Cost And Fair Value Basis [Line Items]
Available-for-sale Securities, debt maturities, within one year, Amortized Cost		37,338
Available-for-sale Securities, debt maturities, after one year through three years, Amortized Cost		380,761
Available-for-sale Securities, debt maturities, after three year through five years, Amortized Cost		351,855
Available-for-sale Securities, debt maturities, after five through ten years, Amortized Cost		698,866
Availably-for-sale Securities, debt maturities, after ten years, Amortized Cost		1,592,209
Available-for-sale Securities, debt maturities, within one year, Fair Value		37,275
Available-for-sale Securities, debt maturities, after one year through three years, Fair Value		372,133
Available-for-sale Securities, debt maturities, after three year through five years, Fair Value		345,895
Available-for-sale Securities, debt maturities, after five through ten years, fair value		689,934
Availably-for-sale Securities, debt maturities, after ten years, Fair Value		1,583,470
Held-to-maturity Securities, debt maturities, after five through ten years, Amortized Cost		478,024
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		2,787,496
Held-to-maturity Securities, debt maturities, after five through ten years, Fair Value		478,491
Held-to-maturity Securities, debt maturities, after ten years, Fair Value		2,777,211
Mortgage Backed Securities [Member]
Schedule Of Debt Securities At Amortized Cost And Fair Value Basis [Line Items]
Available-for-sale Securities, debt maturities, after one year through three years, Amortized Cost		163
Available-for-sale Securities, debt maturities, after three year through five years, Amortized Cost		1,360
Available-for-sale Securities, debt maturities, after five through ten years, Amortized Cost		6,242
Availably-for-sale Securities, debt maturities, after ten years, Amortized Cost		324,334
Available-for-sale Securities, debt maturities, after one year through three years, Fair Value		163
Available-for-sale Securities, debt maturities, after three year through five years, Fair Value		1,365
Available-for-sale Securities, debt maturities, after five through ten years, fair value		6,194
Availably-for-sale Securities, debt maturities, after ten years, Fair Value		313,178
Held-to-maturity Securities, debt maturities, after one year through three years, Amortized Cost		55,351
Held-to-maturity Securities, debt maturities, after five through ten years, Amortized Cost		180,433
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		1,064,149
Held-to-maturity Securities, debt maturities, after one year through three years, Fair Value		55,008
Held-to-maturity Securities, debt maturities, after five through ten years, Fair Value		173,389
Held-to-maturity Securities, debt maturities, after ten years, Fair Value		$ 1,022,286
[1]	Due to the immaterial amount of income recognized on tax-exempt securities, yields were not calculated on a tax-equivalent basis.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.

Available-For-Sale And Held-T_6

Available-For-Sale And Held-To-Maturity Securities (Contractual Maturities) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, within one year, Fair Value	[1]	$ 37,275
Available-for-sale Securities, debt maturities, after one year through five, Fair Value	[1]	719,556
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	696,128
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	1,896,648
Available-for-sale Securities, debt maturities, Fair Value	[1]	3,349,607
Held-to-maturity Securities, debt maturities, after one year through five, Amortized Cost		55,351
Held-to-maturity Securities, debt maturities, after five year through ten, Amortized Cost		658,457
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		3,851,645
Held-to-maturity Securities, Amortized cost	[2]	4,565,453	$ 3,698,098
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, within one year, Fair Value	[1]	1,657
Available-for-sale Securities, debt maturities, after one year through five, Fair Value	[1]	3,508
Available-for-sale Securities, debt maturities, Fair Value	[1]	5,165
State And Municipal Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, within one year, Fair Value	[1]	395
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	18,272
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	50,209
Available-for-sale Securities, debt maturities, Fair Value	[1]	68,876
Corporate Fixed Income Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, within one year, Fair Value	[1]	35,223
Available-for-sale Securities, debt maturities, after one year through five, Fair Value	[1]	714,520
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	427,572
Available-for-sale Securities, debt maturities, Fair Value	[1]	1,177,315
Asset-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	244,090
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	1,533,261
Available-for-sale Securities, debt maturities, Fair Value	[1]	1,777,351
Held-to-maturity Securities, debt maturities, after five year through ten, Amortized Cost		478,024
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		2,787,496
Held-to-maturity Securities, Amortized cost		3,265,520
Mortgage Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, after five through ten years, fair value		6,194
Availably-for-sale Securities, debt maturities, after ten years, Fair Value		313,178
Held-to-maturity Securities, debt maturities, after five year through ten, Amortized Cost		180,433
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		1,064,149
Mortgage Backed Securities [Member] | Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, debt maturities, after one year through five, Fair Value	[1]	1,528
Available-for-sale Securities, debt maturities, after five through ten years, fair value	[1]	6,194
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	243,086
Available-for-sale Securities, debt maturities, Fair Value	[1]	250,808
Held-to-maturity Securities, debt maturities, after five year through ten, Amortized Cost		180,433
Held-to-maturity Securities, debt maturities, after ten years, Amortized Cost		1,064,149
Held-to-maturity Securities, Amortized cost	[2]	1,244,582	1,334,833
Mortgage Backed Securities [Member] | Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	68,823
Available-for-sale Securities, debt maturities, Fair Value	[1]	68,823
Held-to-maturity Securities, debt maturities, after one year through five, Amortized Cost		55,351
Held-to-maturity Securities, Amortized cost	[2]	55,351	$ 58,971
Mortgage Backed Securities [Member] | Non-Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Availably-for-sale Securities, debt maturities, after ten years, Fair Value	[1]	1,269
Available-for-sale Securities, debt maturities, Fair Value	[1]	$ 1,269
[1]	Due to the immaterial amount of income recognized on tax-exempt securities, yields were not calculated on a tax-equivalent basis.
[2]	Held-to-maturity securities are carried in the consolidated statements of financial condition at amortized cost, and the changes in the value of these securities, other than impairment charges, are not reported on the consolidated financial statements.

Available-For-Sale And Held-T_7

Available-For-Sale And Held-To-Maturity Securities (Schedule Of Gross Unrealized Losses And The Estimated Fair Value By Length Of Time In A Loss Position) (Details) $ in Thousands	Sep. 30, 2018USD ($)
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	$ (22,667)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,129,854
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(26,542)
Available-for-sale Securities, Estimated fair value, 12 months or more	634,783
Available-for-sale Securities, Gross unrealized losses, Total	(49,209)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,764,637
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(24,445)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	2,287,199
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	(39,563)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	681,802
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss, Total	(64,008)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total	2,969,001
U.S. Government Agency Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(61)
Available-for-sale Securities, Estimated fair value, Less than 12 months	5,040
Available-for-sale Securities, Gross unrealized losses, Total	(61)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	5,040
State And Municipal Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(4,377)
Available-for-sale Securities, Estimated fair value, 12 months or more	68,481
Available-for-sale Securities, Gross unrealized losses, Total	(4,377)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	68,481
Corporate Fixed Income Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(14,053)
Available-for-sale Securities, Estimated fair value, Less than 12 months	565,671
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(11,672)
Available-for-sale Securities, Estimated fair value, 12 months or more	310,351
Available-for-sale Securities, Gross unrealized losses, Total	(25,725)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	876,022
Asset-Backed Securities [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(7,810)
Available-for-sale Securities, Estimated fair value, Less than 12 months	517,276
Available-for-sale Securities, Gross unrealized losses, Total	(7,810)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	517,276
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(12,298)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	1,675,810
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	(2,460)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	42,507
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss, Total	(14,758)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,718,317
Mortgage Backed Securities [Member] | Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(731)
Available-for-sale Securities, Estimated fair value, Less than 12 months	40,606
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(4,610)
Available-for-sale Securities, Estimated fair value, 12 months or more	188,110
Available-for-sale Securities, Gross unrealized losses, Total	(5,341)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	228,716
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(11,804)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	556,381
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss	(37,103)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	639,295
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss, Total	(48,907)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total	1,195,676
Mortgage Backed Securities [Member] | Commercial [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, 12 months or more	(5,883)
Available-for-sale Securities, Estimated fair value, 12 months or more	67,841
Available-for-sale Securities, Gross unrealized losses, Total	(5,883)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	67,841
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	(343)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	55,008
Held-to-maturity Securities, Continuous Unrealized Loss Position, Aggregate Loss, Total	(343)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value, Total	55,008
Mortgage Backed Securities [Member] | Non-Agency [Member]
Schedule Of Available For Sale And Held To Maturity Securities [Line Items]
Available-for-sale Securities, Gross unrealized losses, Less than 12 months	(12)
Available-for-sale Securities, Estimated fair value, Less than 12 months	1,261
Available-for-sale Securities, Gross unrealized losses, Total	(12)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value, Total	$ 1,261

Bank Loans (Schedule Of Balance

Bank Loans (Schedule Of Balance And Associated Percentage Of Each Major Loan Category In Bank Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 8,344,626		$ 7,014,421
Unamortized loan premium/(discount), net	(13,419)		788
Loans in process	(2,755)		(856)
Unamortized loan fees, net	6,237		872
Allowance for loan losses	(80,700)	$ (73,775)	(67,466)	$ (62,229)	$ (54,202)	$ (45,163)
Bank loans, net	$ 8,253,989		$ 6,947,759
Gross bank loans, Percent	100.00%		100.00%
Commercial And Industrial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 3,127,435		$ 2,437,938
Allowance for loan losses	$ (64,580)	(59,572)	$ (54,474)	(47,152)	(40,805)	(35,127)
Gross bank loans, Percent	37.50%		34.80%
Residential Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 2,792,269		$ 2,593,576
Allowance for loan losses	$ (10,493)	(9,328)	$ (8,430)	(7,135)	(5,569)	(2,660)
Gross bank loans, Percent	33.50%		37.00%
Securities-Based Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 1,836,450		$ 1,819,206
Allowance for loan losses	$ (1,923)	(1,928)	$ (2,088)	(3,312)	(3,600)	(3,094)
Gross bank loans, Percent	22.00%		25.90%
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 328,814		$ 116,258
Allowance for loan losses	$ (1,762)	(1,672)	$ (1,520)	(1,027)	(932)	(1,363)
Gross bank loans, Percent	3.90%		1.70%
Home Equity Lines Of Credit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 29,118		$ 15,039
Allowance for loan losses	$ (229)	(229)	$ (162)	(271)	(283)	(371)
Gross bank loans, Percent	0.30%		0.20%
Construction And Land [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 120,969		$ 7,896
Allowance for loan losses	$ (903)	(303)	$ (100)	(233)	(224)	(232)
Gross bank loans, Percent	1.40%		0.10%
Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross bank loans	$ 109,571		$ 24,508
Allowance for loan losses	$ (11)	$ (13)	$ (16)	$ (103)	$ (105)	$ (129)
Gross bank loans, Percent	1.40%		0.30%

Bank Loans (Narrative) (Details

Bank Loans (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans held for sale, at lower of cost or market	$ 262,063		$ 262,063		$ 226,068
Gains (losses) recognized from sale of loans	2,600	$ 3,200	7,800	$ 9,400
Impaired loans more than 90 days past due	24,200		24,200		29,200
Troubled debt restructurings	9,100		9,100		9,100
Specific allowance	$ 8,701		$ 8,701		$ 9,105
Collateralized loan portfolio	98.60%		98.60%		97.20%
Stifel Financial Corp. [Member] | Executive Officers Directors and Their Affiliates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans outstanding amount	$ 25,200		$ 25,200		$ 8,400
Stifel Bancorp [Member] | Executive Officers Directors and Their Affiliates [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans outstanding amount	$ 4,000		$ 4,000		$ 4,000

Bank Loans (Activity In The All

Bank Loans (Activity In The Allowance For Loan Losses By Portfolio Segment) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	$ 73,775	$ 54,202	$ 67,466	$ 45,163
Provision	6,924	7,990	13,244	19,980
Charge-offs			(14)	(2,953)
Recoveries	1	37	4	39
Ending Balance	80,700	62,229	80,700	62,229
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	59,572	40,805	54,474	35,127
Provision	5,008	6,312	10,118	12,239
Charge-offs			(12)	(250)
Recoveries		35		36
Ending Balance	64,580	47,152	64,580	47,152
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	1,928	3,600	2,088	3,094
Provision	(5)	(288)	(165)	218
Ending Balance	1,923	3,312	1,923	3,312
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	9,328	5,569	8,430	2,660
Provision	1,165	1,566	2,063	4,475
Ending Balance	10,493	7,135	10,493	7,135
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	1,672	932	1,520	1,363
Provision	90	95	242	2,367
Charge-offs				(2,703)
Ending Balance	1,762	1,027	1,762	1,027
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	229	283	162	371
Provision		(13)	65	(102)
Recoveries		1	2	2
Ending Balance	229	271	229	271
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	303	224	100	232
Provision	600	9	803	1
Ending Balance	903	233	903	233
Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	13	105	16	129
Provision	(3)	(3)	(5)	(27)
Charge-offs			(2)
Recoveries	1	1	2	1
Ending Balance	11	103	11	103
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Beginning Balance	730	2,684	676	2,187
Provision	69	312	123	809
Ending Balance	$ 799	$ 2,996	$ 799	$ 2,996

Bank Loans (Recorded Balances O

Bank Loans (Recorded Balances Of Loans and Amount Of Allowance Allocated Based Upon Impairment Method by Portfolio Segment) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	$ 8,701		$ 9,105
Allowance for Loan Losses, Collectively Evaluated for Impairment	71,999		58,361
Allowance for Loan Losses, Total	80,700	$ 73,775	67,466	$ 62,229	$ 54,202	$ 45,163
Recorded Investment in Loans, Individually Evaluated for Impairment	24,247		29,213
Recorded Investment in Loans, Collectively Evaluated for Impairment	8,320,379		6,985,208
Recorded Investment in Loans, Total	8,344,626		7,014,421
Residential Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	24		24
Allowance for Loan Losses, Collectively Evaluated for Impairment	10,469		8,406
Allowance for Loan Losses, Total	10,493	9,328	8,430	7,135	5,569	2,660
Recorded Investment in Loans, Individually Evaluated for Impairment	328		171
Recorded Investment in Loans, Collectively Evaluated for Impairment	2,791,941		2,593,405
Recorded Investment in Loans, Total	2,792,269		2,593,576
Commercial And Industrial [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment	8,677		9,059
Allowance for Loan Losses, Collectively Evaluated for Impairment	55,903		45,415
Allowance for Loan Losses, Total	64,580	59,572	54,474	47,152	40,805	35,127
Recorded Investment in Loans, Individually Evaluated for Impairment	23,630		28,856
Recorded Investment in Loans, Collectively Evaluated for Impairment	3,103,805		2,409,082
Recorded Investment in Loans, Total	3,127,435		2,437,938
Securities-Based Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,923		2,088
Allowance for Loan Losses, Total	1,923	1,928	2,088	3,312	3,600	3,094
Recorded Investment in Loans, Collectively Evaluated for Impairment	1,836,450		1,819,206
Recorded Investment in Loans, Total	1,836,450		1,819,206
Commercial Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	1,762		1,520
Allowance for Loan Losses, Total	1,762	1,672	1,520	1,027	932	1,363
Recorded Investment in Loans, Collectively Evaluated for Impairment	328,814		116,258
Recorded Investment in Loans, Total	328,814		116,258
Home Equity Lines Of Credit [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment			20
Allowance for Loan Losses, Collectively Evaluated for Impairment	229		142
Allowance for Loan Losses, Total	229	229	162	271	283	371
Recorded Investment in Loans, Individually Evaluated for Impairment	231		184
Recorded Investment in Loans, Collectively Evaluated for Impairment	28,887		14,855
Recorded Investment in Loans, Total	29,118		15,039
Construction And Land [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	903		100
Allowance for Loan Losses, Total	903	303	100	233	224	232
Recorded Investment in Loans, Collectively Evaluated for Impairment	120,969		7,896
Recorded Investment in Loans, Total	120,969		7,896
Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Individually Evaluated for Impairment			2
Allowance for Loan Losses, Collectively Evaluated for Impairment	11		14
Allowance for Loan Losses, Total	11	13	16	103	105	129
Recorded Investment in Loans, Individually Evaluated for Impairment	58		2
Recorded Investment in Loans, Collectively Evaluated for Impairment	109,513		24,506
Recorded Investment in Loans, Total	109,571		24,508
Qualitative [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Allowance for Loan Losses, Collectively Evaluated for Impairment	799		676
Allowance for Loan Losses, Total	$ 799	$ 730	$ 676	$ 2,996	$ 2,684	$ 2,187

Bank Loans (Loans That Were Ind

Bank Loans (Loans That Were Individually Evaluated For Impairment By Portfolio Segment) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Impaired [Line Items]
Unpaid Contractual Principal Balance	$ 24,945	$ 29,888
Recorded Investment with No Allowance	486	5,211
Recorded Investment with Allowance	23,761	24,002
Total Recorded Investment	24,247	29,213
Related Allowance	8,701	9,105
Average Recorded Investment	24,434	30,756
Commercial And Industrial [Member]
Financing Receivable Impaired [Line Items]
Unpaid Contractual Principal Balance	23,630	28,856
Recorded Investment with No Allowance	196	5,211
Recorded Investment with Allowance	23,434	23,645
Total Recorded Investment	23,630	28,856
Related Allowance	8,677	9,059
Average Recorded Investment	23,783	30,277
Residential Real Estate [Member]
Financing Receivable Impaired [Line Items]
Unpaid Contractual Principal Balance	353	171
Recorded Investment with No Allowance	80
Recorded Investment with Allowance	248	171
Total Recorded Investment	328	171
Related Allowance	24	24
Average Recorded Investment	355	174
Other [Member]
Financing Receivable Impaired [Line Items]
Unpaid Contractual Principal Balance	731	677
Recorded Investment with No Allowance	26
Recorded Investment with Allowance	32	2
Total Recorded Investment	58	2
Related Allowance		2
Average Recorded Investment	60	5
Home Equity Lines Of Credit [Member]
Financing Receivable Impaired [Line Items]
Unpaid Contractual Principal Balance	231	184
Recorded Investment with No Allowance	184
Recorded Investment with Allowance	47	184
Total Recorded Investment	231	184
Related Allowance		20
Average Recorded Investment	$ 236	$ 300

Bank Loans (Aging Of The Record

Bank Loans (Aging Of The Recorded Investment In Past Due Loans) (Details) - USD ($)		Sep. 30, 2018		Dec. 31, 2017
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 18,699,000		$ 19,961,000
Current Balance		8,325,927,000		6,994,460,000
Recorded Investment in Loans, Total		8,344,626,000		7,014,421,000
Non-Accrual		15,142,000	[1]	20,090,000	[2]
Restructured		9,105,000	[1]	9,123,000	[2]
Total		24,247,000	[1]	29,213,000	[2]
Loans past due 90 days and still accruing interest		0		0
30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		3,792,000		19,961,000
90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		14,907,000
Residential Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		3,929,000		7,892,000
Current Balance		2,788,340,000		2,585,684,000
Recorded Investment in Loans, Total		2,792,269,000		2,593,576,000
Non-Accrual	[1]	159,000
Restructured		169,000	[1]	171,000	[2]
Total		328,000	[1]	171,000	[2]
Residential Real Estate [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		3,745,000		7,892,000
Residential Real Estate [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		184,000
Commercial And Industrial [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		14,656,000		11,883,000
Current Balance		3,112,779,000		2,426,055,000
Recorded Investment in Loans, Total		3,127,435,000		2,437,938,000
Non-Accrual		14,694,000	[1]	19,904,000	[2]
Restructured		8,936,000	[1]	8,952,000	[2]
Total		23,630,000	[1]	28,856,000	[2]
Commercial And Industrial [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due				11,883,000
Commercial And Industrial [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		14,656,000
Securities-Based Loans [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Current Balance		1,836,450,000		1,819,206,000
Recorded Investment in Loans, Total		1,836,450,000		1,819,206,000
Commercial Real Estate [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Current Balance		328,814,000		116,258,000
Recorded Investment in Loans, Total		328,814,000		116,258,000
Home Equity Lines Of Credit [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		47,000		184,000
Current Balance		29,071,000		14,855,000
Recorded Investment in Loans, Total		29,118,000		15,039,000
Non-Accrual		231,000	[1]	184,000	[2]
Total		231,000	[1]	184,000	[2]
Home Equity Lines Of Credit [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		47,000		184,000
Construction And Land [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Current Balance		120,969,000		7,896,000
Recorded Investment in Loans, Total		120,969,000		7,896,000
Other [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		67,000		2,000
Current Balance		109,504,000		24,506,000
Recorded Investment in Loans, Total		109,571,000		24,508,000
Non-Accrual		58,000	[1]	2,000	[2]
Total		58,000	[1]	2,000	[2]
Other [Member] | 30 - 89 Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due				$ 2,000
Other [Member] | 90 or More Days Past Due [Member]
Financing Receivable Recorded Investment Past Due [Line Items]
Total Past Due		$ 67,000
[1]	There were no loans past due 90 days and still accruing interest at September 30, 2018.
[2]	There were no loans past due 90 days and still accruing interest at December 31, 2017.

Bank Loans (Risk Category Of Lo

Bank Loans (Risk Category Of Loan Portfolio) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	$ 8,344,626	$ 7,014,421
Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	8,285,497	6,960,969
Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	34,882	22,752
Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	24,236	30,700
Doubtful [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	11
Residential Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	2,792,269	2,593,576
Residential Real Estate [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	2,791,627	2,593,096
Residential Real Estate [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	394	309
Residential Real Estate [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	248	171
Commercial And Industrial [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	3,127,435	2,437,938
Commercial And Industrial [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	3,069,237	2,385,152
Commercial And Industrial [Member] | Special Mention [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	34,488	22,443
Commercial And Industrial [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	23,710	30,343
Securities-Based Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	1,836,450	1,819,206
Securities-Based Loans [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	1,836,450	1,819,206
Commercial Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	328,814	116,258
Commercial Real Estate [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	328,814	116,258
Home Equity Lines Of Credit [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	29,118	15,039
Home Equity Lines Of Credit [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	28,887	14,855
Home Equity Lines Of Credit [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	231	184
Construction And Land [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	120,969	7,896
Construction And Land [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	120,969	7,896
Other [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	109,571	24,508
Other [Member] | Pass [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	109,513	24,506
Other [Member] | Substandard [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	47	$ 2
Other [Member] | Doubtful [Member]
Financing Receivable Recorded Investment [Line Items]
Total risk category of loan portfolio	$ 11

Goodwill And Intangible Asset_2

Goodwill And Intangible Assets (Carrying Amount Of Goodwill And Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill, Beginning balance			$ 968,834
Goodwill, Adjustments			56,880
Goodwill, Ending balance	$ 1,025,714		1,025,714
Intangible assets, Beginning balance			109,627
Intangible assets, Net Additions			18,037
Intangible assets, Amortization	(3,000)	$ (2,900)	(8,741)	$ (9,092)
Intangible assets, Ending balance	118,923		118,923
Global Wealth Management [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill, Beginning balance			276,477
Goodwill, Adjustments			54,969
Goodwill, Ending balance	331,446		331,446
Intangible assets, Beginning balance			44,525
Intangible assets, Net Additions			17,180
Intangible assets, Amortization			(3,662)
Intangible assets, Ending balance	58,043		58,043
Institutional Group [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill, Beginning balance			692,357
Goodwill, Adjustments			1,911
Goodwill, Ending balance	694,268		694,268
Intangible assets, Beginning balance			65,102
Intangible assets, Net Additions			857
Intangible assets, Amortization			(5,079)
Intangible assets, Ending balance	$ 60,880		$ 60,880

Goodwill And Intangible Asset_3

Goodwill And Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Mar. 19, 2018	Dec. 31, 2017
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill	$ 1,025,714		$ 1,025,714			$ 968,834
Amortization of intangible assets	3,000	$ 2,900	$ 8,741	$ 9,092
Customer Relationships [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets			10 years 8 months 12 days
Trade Name [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets			9 years 8 months 12 days
Non-Compete Agreements [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets			8 years 9 months 18 days
BBI Intangibles [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Weighted-average remaining lives of intangible assets			5 years
Ziegler [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill	19,000		$ 19,000
Ziegler [Member] | Customer Relationships and Non-Compete Agreements [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Identifiable intangible assets					$ 9,500
Business Bancshares, Inc. [Member]
Schedule of Goodwill and Intangible Assets [Line Items]
Goodwill and intangible assets	$ 46,400		$ 46,400

Goodwill And Intangible Asset_4

Goodwill And Intangible Assets (Intangible Assets Subject To Amortization) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		$ 193,602	$ 175,716
Accumulated Amortization		76,797	68,207
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		156,240	146,986
Accumulated Amortization		62,822	55,809
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		24,713	24,713
Accumulated Amortization		11,373	10,228
Investment Banking Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		1,431	1,419
Accumulated Amortization		1,214	968
Non-Compete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value		2,603	2,598
Accumulated Amortization		1,388	$ 1,202
Estimated BBI Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	[1]	$ 8,615
[1]	See discussion regarding the allocation of the estimated goodwill and intangibles recorded for the BBI acquisition.

Goodwill And Intangible Asset_5

Goodwill And Intangible Assets (Amortization Expense In Future Periods) (Details) $ in Thousands	Sep. 30, 2018USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
Remainder of 2018	$ 3,382
2,019	12,974
2,020	12,757
2,021	12,258
2,022	11,798
Thereafter	63,636
Future amortization expense total	$ 116,805

Borrowings and Federal Home L_2

Borrowings and Federal Home Loan Bank Advances (Narrative) (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2018USD ($)item	Sep. 30, 2018USD ($)item
Short-term Debt [Line Items]
Uncommitted secured lines of credit		$ 1,000,000,000
Number of banks | item	6	6
Daily borrowings under our uncommitted secured lines	$ 391,000,000	$ 391,000,000
Compensating balances	0	0
Federal home loan advances, floating-rate	1,100,000,000	$ 1,100,000,000
Stifel Bancorp [Member]
Short-term Debt [Line Items]
Notes maturity year		2,043
Notes payable	134,800,000	$ 134,800,000
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Committed revolving credit facility with bank and broker dealer - subsidiary	200,000,000	$ 200,000,000
Credit facility expiration date		2020-03
LIBOR rate		1.75%
Outstanding credit facility	0	$ 0
Stifel Credit Facility [Member]
Short-term Debt [Line Items]
Committed revolving credit facility with bank and broker dealer - subsidiary	250,000,000	$ 250,000,000
Credit facility expiration date		2019-06
Outstanding credit facility	$ 0	$ 0
Credit agreement maturity days		364 days
Company Owned Securities [Member]
Short-term Debt [Line Items]
Uncommitted secured lines of credit		$ 0
Federal Home Loan Bank advances [Member]
Short-term Debt [Line Items]
Weighted average interest rate on borrowings	1.65%	1.52%

Senior Notes (Summary of Senior

Senior Notes (Summary of Senior Notes) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017	Oct. 31, 2017	Dec. 31, 2015	Jul. 31, 2014
Debt Instrument [Line Items]
Long-term Debt, gross		$ 1,025,000	$ 1,025,000
Debt issuance costs, net		(9,286)	(10,060)
Long-term Debt		1,015,714	1,014,940
Senior notes 4.250% due 2024 [Member]
Debt Instrument [Line Items]
Long-term Debt, gross	[1]	500,000	500,000
Long-term Debt						$ 300,000
Senior notes 3.50% due 2020 [Member]
Debt Instrument [Line Items]
Long-term Debt, gross	[2]	300,000	300,000
Long-term Debt					$ 300,000
Senior notes 5.20% due 2047 [Member]
Debt Instrument [Line Items]
Long-term Debt, gross	[3]	$ 225,000	$ 225,000
Long-term Debt				$ 200,000
[1]	In July 2014, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 4.250% senior notes due July 2024. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption. In July 2016, we issued an additional $200.0 million in aggregate principal amount of 4.25% senior notes due 2024.
[2]	In December 2015, we sold in a registered underwritten public offering, $300.0 million in aggregate principal amount of 3.50% senior notes due December 2020. Interest on these senior notes is payable semi-annually in arrears. We may redeem the notes in whole or in part, at our option, at a redemption price equal to 100% of their principal amount, plus a “make-whole” premium and accrued and unpaid interest, if any, to the date of redemption.
[3]	(3)In October 2017, we completed the pricing of a registered underwritten public offering of $200.0 million in aggregate principal amount of 5.20% senior notes due October 2047. Interest on the senior notes is payable quarterly in arrears on January 15, April 15, July 15, and October 15. On or after October 15, 2022, we may redeem some or all of the senior notes at any time at a redemption price equal to 100% of the principal amount of the notes being redeemed plus accrued interest thereon to the redemption date. On October 27, 2017, we completed the sale of an additional $25.0 million aggregate principal amount of Notes pursuant to the over-allotment option.

Senior Notes (Summary of Seni_2

Senior Notes (Summary of Senior Notes) (Parenthetical) (Details) - USD ($) $ in Thousands	Oct. 27, 2017	Jul. 31, 2016	Sep. 30, 2018	Dec. 31, 2017	Oct. 31, 2017	Dec. 31, 2015	Jul. 31, 2014
Debt Instrument [Line Items]
Stated interest rate			4.25%
Long-term Debt			$ 1,015,714	$ 1,014,940
Debt instrument, maturity date			Dec. 31, 2024
Senior notes 4.250% due 2024 [Member]
Debt Instrument [Line Items]
Stated interest rate			4.25%				4.25%
Long-term Debt							$ 300,000
Debt instrument, maturity date			Jul. 31, 2024
Redemption price, percentage of principal amount			100.00%
Additional issuance of long-term debt		$ 200,000
Senior notes 3.50% due 2020 [Member]
Debt Instrument [Line Items]
Stated interest rate			3.50%			3.50%
Long-term Debt						$ 300,000
Debt instrument, maturity date			Dec. 31, 2020
Redemption price, percentage of principal amount			100.00%
Senior notes 5.20% due 2047 [Member]
Debt Instrument [Line Items]
Stated interest rate			5.20%		5.20%
Long-term Debt					$ 200,000
Debt instrument, maturity date			Oct. 31, 2047
Redemption price, percentage of principal amount			100.00%
Additional issuance of long-term debt	$ 25,000

Senior Notes (Schedule Of Corpo

Senior Notes (Schedule Of Corporate Debt Principal Maturities) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Long-term Debt	$ 1,015,714	$ 1,014,940
Non Recourse Debt [Member]
Debt Instrument [Line Items]
2,020	300,000
Thereafter	725,000
Long-term Debt	$ 1,025,000

Bank Deposits (Schedule Of Depo

Bank Deposits (Schedule Of Deposits) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Deposits Liabilities Balance Sheet Reported Amounts [Abstract]
Money market and savings accounts	$ 11,950,269	$ 13,219,675
Certificates of deposit	1,970,318	1,575
Demand deposits (interest-bearing)	465,366	184,829
Demand deposits (non-interest-bearing)	116,999	5,856
Bank deposits	$ 14,502,952	$ 13,411,935

Bank Deposits (Narrative) (Deta

Bank Deposits (Narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Bank Deposits [Line Items]
Weighted average interest rate on deposits	0.49%	0.10%
Brokerage Customers Deposits [Member]
Bank Deposits [Line Items]
Deposits of related parties	$ 13,600	$ 13,400
Stifel Nicolaus [Member]
Bank Deposits [Line Items]
Interest bearing and time deposits of executive officers, directors, and affiliates	$ 3.8	$ 0.2

Bank Deposits (Scheduled Maturi

Bank Deposits (Scheduled Maturities of Certificates of Deposit) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Deposits Liabilities Balance Sheet Reported Amounts [Abstract]
Within one year	$ 5,617	$ 438
One to three years	544	148
Three to five years	127
Certificates of deposit, less than $100	6,288	586
Within one year	1,740,855	651
One to three years	193,185	338
Three to five years	29,990
Certificates of deposit, $100 and greater	1,964,030	989
Total certificates of deposit	$ 1,970,318	$ 1,575

Derivative Instruments And He_3

Derivative Instruments And Hedging Activities (Schedule Of Notional Values And Fair Values Of Derivative Instruments) (Details) - Cash Flow Interest Rate Contracts [Member] - Designated As Hedging Instrument [Member] - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Asset Derivatives, Notional Value	$ 540,000,000	$ 540,000,000
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Asset Derivatives, Fair Value	$ 11,117,000	$ 7,995,000

Derivative Instruments And He_4

Derivative Instruments And Hedging Activities (Narrative) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
General Discussion Of Derivative Instruments And Hedging Activities [Abstract]
Average remaining life of interest rate swap agreements	1 year 3 months 18 days
Estimated derivatives to be reclassified as interest income	$ 4.9

Derivative Instruments And He_5

Derivative Instruments And Hedging Activities (Schedule Of Derivative Instruments In Consolidated Statements Of Operations) (Details) - Cash Flow Interest Rate Contracts [Member] - Interest Expense [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized in OCI (Effectiveness)	$ (603)	$ 928	$ (5,823)	$ 3,504
Gain/(Loss) Reclassified From OCI Into Income	$ 1,504	$ 724	$ 3,262	$ (810)

Disclosures About Offsetting _3

Disclosures About Offsetting Assets And Liabilities (Financial Assets And Derivative Assets That Are Subject To Offset) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Offsetting [Abstract]
Gross amounts of recognized assets, Securities borrowing	[1]	$ 170,165	$ 132,776
Net amounts presented in the Statement of Financial Condition, Securities borrowing	[1]	170,165	132,776
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities borrowing	[1]	(47,974)	(78,474)
Gross amounts not offset in the Statement of Financial Position, Collateral received, Securities borrowing	[1]	(110,088)	(37,248)
Securities borrowed, Net amount	[1]	12,103	17,054
Gross amounts of recognized assets, Reverse repurchase agreements	[2]	622,361	512,220
Net amounts presented in the Statement of Financial Condition, Securities purchased under agreements to resell	[2]	622,361	512,220
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities purchased under agreements to resell	[2]	(261,773)	(233,624)
Gross amounts not offset in the Statement of Financial Position, Collateral received, Securities purchased under agreements to resell	[2]	(356,842)	(266,008)
Securities purchased under agreements to resell, Net amount	[2]	3,746	12,588
Gross amounts of recognized assets, Cash flow interest rate contracts		11,117	7,995
Net amounts presented in the Statement of Financial Condition, Cash flow interest rate contracts		11,117	7,995
Cash flow interest rate contracts, Net amount		11,117	7,995
Gross amounts of recognized assets		803,643	652,991
Net amounts presented in the Statements of Financial Condition		803,643	652,991
Gross amounts not offset in the Statement of Financial Position		(309,747)	(312,098)
Gross amounts not offset in the Statement of Financial Position, Collateral received		(466,930)	(303,256)
Net amount		$ 26,966	$ 37,637
[1]	Securities borrowing transactions are included in receivables from brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on receivables from brokers, dealers, and clearing organizations.
[2]	Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.

Disclosures About Offsetting _4

Disclosures About Offsetting Assets And Liabilities (Financial Assets And Derivative Assets That Are Subject To Offset) (Details) (Parenthetical) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Offsetting Assets [Line Items]
Fair value of securities pledged as collateral	[1]	$ 356,842	$ 266,008
Fair Value Of Securities Pledged As Collateral [Member]
Offsetting Assets [Line Items]
Fair value of securities pledged as collateral		$ 621,500	$ 509,400
[1]	Collateral received includes securities received by our company from the counterparty. These securities are not included on the consolidated statements of financial condition unless there is an event of default. The fair value of securities pledged as collateral was $621.5 million and $509.4 million at September 30, 2018 and December 31, 2017, respectively.

Disclosures About Offsetting _5

Disclosures About Offsetting Assets And Liabilities (Financial Liabilities And Derivative Liabilities That Are Subject To Offset) (Details) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Offsetting [Abstract]
Gross amounts of recognized liabilities, Securities lending	[1]	$ (691,150)	$ (219,782)
Net amounts presented in the Statement of Financial Condition, Securities lending	[1]	(691,150)	(219,782)
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities lending	[1]	47,974	78,474
Gross amounts not offset in the Statement of Financial Position, Collateral pledged, Securities lending	[1]	616,157	133,772
Securities lending, Net amount	[1]	(27,019)	(7,536)
Gross amounts of recognized liabilities, Securities purchased under agreements to resell	[2]	(495,484)	(233,704)
Net amounts presented in the Statement of Financial Condition, Securities purchased under agreements to resell	[2]	(495,484)	(233,704)
Gross amounts not offset in the Statement of Financial Position, Financial instruments, Securities purchased under agreements to resell	[2]	261,773	233,624
Gross amounts not offset in the Statement of Financial Position, Collateral pledged, Securities purchased under agreements to resell	[2]	233,711	80
Gross amounts of recognized liabilities		(1,186,634)	(453,486)
Net amounts presented in the Statement of Financial Condition		(1,186,634)	(453,486)
Gross amounts not offset in the Statement of Financial Position, Financial instruments		309,747	312,098
Gross amounts not offset in the Statement of Financial Condition, Collateral pledged		849,868	133,852
Net amount		$ (27,019)	$ (7,536)
[1]	Securities lending transactions are included in payables to brokers, dealers, and clearing organizations on the consolidated statements of financial condition. See Note 3 in the notes to consolidated financial statements for additional information on payables to brokers, dealers, and clearing organizations.
[2]	Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Disclosures About Offsetting _6

Disclosures About Offsetting Assets And Liabilities (Financial Liabilities And Derivative Liabilities That Are Subject To Offset) (Details) (Parenthetical) - USD ($) $ in Thousands		Sep. 30, 2018	Dec. 31, 2017
Offsetting Liabilities [Line Items]
Fair value of securities pledged as collateral to counter party	[1]	$ 233,711	$ 80
U.S. Government Agency Securities And U.S. Government Securities And Corporate Fixed Income Securities [Member] | Fair Value Of Securities Pledged As Collateral [Member]
Offsetting Liabilities [Line Items]
Fair value of securities pledged as collateral to counter party		$ 522,400	$ 241,400
[1]	Collateral pledged includes the fair value of securities pledged by our company to the counter party. These securities are included on the consolidated statements of financial condition unless we default. Collateral pledged by our company to the counter party includes U.S. government agency securities, U.S. government securities, and corporate fixed income securities with market values of $522.4 million and $241.4 million at September 30, 2018 and December 31, 2017, respectively.

Regulatory Capital Requiremen_3

Regulatory Capital Requirements (Narrative) (Details) $ in Millions	Sep. 30, 2018USD ($)
Our Other Broker-Dealer Subsidiaries
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Ratio of indebtedness to net capital	15
Stifel Nicolaus [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Aggregate debit balances	20.00%
Net capital	$ 355.9
Excess of minimum required net capital	320.4
Stifel Financial Corp. [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Net capital under the alternative method	$ 1
Aggregate debit balances	2.00%

Regulatory Capital Requiremen_4

Regulatory Capital Requirements (Schedule Of Total Risk-Based, Tier 1 Risk-Based, And Tier 1 Leverage Ratios) (Details) $ in Thousands	Sep. 30, 2018USD ($)
Stifel Financial Corp. [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 2,081,840
Tier 1 capital, Actual Ratio	18.00%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 695,439
Tier 1 capital For Capital Adequacy Purposes, Ratio	6.00%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 927,252
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Total capital, Actual Amount	$ 2,232,951
Total capital, Actual Ratio	19.30%
Total capital For Capital Adequacy Purposes, Amount	$ 927,252
Total capital For Capital Adequacy Purposes, Ratio	8.00%
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 1,159,066
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 leverage, Actual Amount	$ 2,081,840
Tier 1 leverage, Actual Ratio	9.60%
Tier 1 leverage For Capital Adequacy Purposes, Amount	$ 864,465
Tier 1 leverage For Capital Adequacy Purposes, Ratio	4.00%
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 1,080,581
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%
Stifel Financial Corp. [Member] | Common Stock [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 1,931,840
Tier 1 capital, Actual Ratio	16.70%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 521,580
Tier 1 capital For Capital Adequacy Purposes, Ratio	4.50%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 753,393
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%
Stifel Bank & Trust [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 1,142,936
Tier 1 capital, Actual Ratio	14.20%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 481,939
Tier 1 capital For Capital Adequacy Purposes, Ratio	6.00%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 642,585
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Total capital, Actual Amount	$ 1,223,636
Total capital, Actual Ratio	15.20%
Total capital For Capital Adequacy Purposes, Amount	$ 642,585
Total capital For Capital Adequacy Purposes, Ratio	8.00%
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 803,231
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 leverage, Actual Amount	$ 1,142,936
Tier 1 leverage, Actual Ratio	7.00%
Tier 1 leverage For Capital Adequacy Purposes, Amount	$ 651,837
Tier 1 leverage For Capital Adequacy Purposes, Ratio	4.00%
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 814,797
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%
Stifel Bank & Trust [Member] | Common Stock [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 1,142,936
Tier 1 capital, Actual Ratio	14.20%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 361,454
Tier 1 capital For Capital Adequacy Purposes, Ratio	4.50%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 522,100
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%
Stifel Bank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 75,385
Tier 1 capital, Actual Ratio	13.80%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 32,888
Tier 1 capital For Capital Adequacy Purposes, Ratio	6.00%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 43,851
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	8.00%
Total capital, Actual Amount	$ 82,246
Total capital, Actual Ratio	15.00%
Total capital For Capital Adequacy Purposes, Amount	$ 43,851
Total capital For Capital Adequacy Purposes, Ratio	8.00%
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 54,814
Total capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	10.00%
Tier 1 leverage, Actual Amount	$ 75,385
Tier 1 leverage, Actual Ratio	12.50%
Tier 1 leverage For Capital Adequacy Purposes, Amount	$ 24,137
Tier 1 leverage For Capital Adequacy Purposes, Ratio	4.00%
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 30,171
Tier 1 leverage To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	5.00%
Stifel Bank [Member] | Common Stock [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 capital, Actual Amount	$ 75,385
Tier 1 capital, Actual Ratio	13.80%
Tier 1 capital For Capital Adequacy Purposes, Amount	$ 24,666
Tier 1 capital For Capital Adequacy Purposes, Ratio	4.50%
Tier 1 capital To Be Well Capitalized Under Prompt Corrective Action Provisions, Amount	$ 35,629
Tier 1 To Be Well Capitalized Under Prompt Corrective Action Provisions, Ratio	6.50%

Revenues from Contracts with _3

Revenues from Contracts with Customers (Schedule of Total Revenues Separated between Revenues from Contracts with Customers and Other Sources of Revenues) (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017
Revenues:
Revenue from contracts with customers	[1]	$ 532,144			$ 1,605,149
Other	[1]	4,394			11,908
Total revenue from contracts with customers		532,165			1,605,150
Other sources of revenue:
Interest		169,760		$ 117,862	461,915		$ 327,766
Principal transactions		83,152		87,010	269,918		299,570
Other		1,733			6,649
Total revenues		786,810		738,794	2,343,632		2,172,512
Commissions [Member]
Revenues:
Revenue from contracts with customers		158,016		162,612	490,693		510,150
Investment Banking [Member]
Revenues:
Revenue from contracts with customers		169,012		181,904	506,437		494,017
Asset Management and Service Fees [Member]
Revenues:
Revenue from contracts with customers		$ 200,743	[1]	$ 179,848	$ 596,112	[1]	$ 515,501
[1]	Excludes revenue included in the Other segment.

Revenues from Contracts with _4

Revenues from Contracts with Customers (Revenues from Contracts with Customers Disaggregated by Major Business Activity and Primary Geographic Regions) (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017
Disaggregation Of Revenue [Line Items]
Commissions	[1]	$ 158,015			$ 490,692
Revenue from contracts with customers	[1]	532,144			1,605,149
Other	[1]	4,394			11,908
Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]	93,275			246,044
Advisory Fees [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]	75,717			260,393
Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers		200,743	[1]	$ 179,848	596,112	[1]	$ 515,501
Global Wealth Management [Member]
Disaggregation Of Revenue [Line Items]
Commissions	[1]	117,795			355,129
Revenue from contracts with customers	[1]	330,646			986,577
Other	[1]	4,394			11,908
Global Wealth Management [Member] | Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]	7,722			23,378
Global Wealth Management [Member] | Advisory Fees [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]				81
Global Wealth Management [Member] | Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	200,735			596,081
Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Commissions	[1]	40,220			135,563
Revenue from contracts with customers	[1]	201,498			618,572
Institutional Group [Member] | Capital Raising [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]	85,553			222,666
Institutional Group [Member] | Advisory Fees [Member]
Disaggregation Of Revenue [Line Items]
Investment banking	[1]	75,717			260,312
Institutional Group [Member] | Asset Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	8			31
United States [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	503,028			1,508,724
United States [Member] | Global Wealth Management [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	330,646			986,577
United States [Member] | Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	172,382			522,147
Europe [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	28,197			92,029
Europe [Member] | Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	28,197			92,029
Other [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	919			4,396
Other [Member] | Institutional Group [Member]
Disaggregation Of Revenue [Line Items]
Revenue from contracts with customers	[1]	$ 919			$ 4,396
[1]	Excludes revenue included in the Other segment.

Revenues from Contracts with _5

Revenues from Contracts with Customers (Narrative) (Details) - USD ($)	3 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Revenue From Contract With Customer [Abstract]
Receivables related to contract with customers	$ 146,700,000	$ 96,000,000
Impairment related to receivables	0
Deferred Revenue	$ 10,200,000

Interest Income And Interest _3

Interest Income And Interest Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest Income Expense Net [Abstract]
Bank loans, net	$ 78,766	$ 54,006	$ 210,790	$ 147,495
Investment securities	66,825	48,072	185,263	136,123
Margin balances	13,066	9,919	36,322	27,124
Financial instruments owned	5,733	4,371	15,645	12,953
Other	5,370	1,494	13,895	4,071
Total interest income	169,760	117,862	461,915	327,766
Bank deposits	25,856	4,770	49,329	8,424
Senior notes	11,248	8,655	33,488	24,935
Federal Home Loan Bank advances	4,232	1,255	10,579	5,771
Other	7,132	2,945	18,804	11,035
Total interest expense	$ 48,468	$ 17,625	$ 112,200	$ 50,165

Employee Incentive, Deferred _2

Employee Incentive, Deferred Compensation, And Retirement Plans (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized to grant			5,300,000
Stock-based compensation			$ 75,382	$ 81,613
Contributions to the Profit Sharing Plan	$ 3,400	$ 1,800	$ 10,100	5,500
Minimum [Member] | Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Maximum [Member] | Deferred Compensation Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			8 years
Incentive Stock Award Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	31,700	$ 32,500	$ 82,500	$ 98,100
Incentive Stock Award Plans [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Incentive Stock Award Plans [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to non-vested options	$ 292,200		$ 292,200
Weighted-average period, compensation cost expected to recognized, in years			2 years 10 months 24 days
Restricted Stock Units (RSUs) [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
Restricted Stock Units (RSUs) [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years
Restricted Stock Units and Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock awards outstanding	16,600,000		16,600,000
Unvested stock awards outstanding	12,900,000		12,900,000
Performance-based Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total number of stock awards outstanding	600,000		600,000
Unvested stock awards outstanding	600,000		600,000
Performance-based Restricted Stock Units [Member] | One to Four Years [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earned award vested			80.00%
Performance-based Restricted Stock Units [Member] | Fifth Year [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of earned award vested			20.00%
Performance-based Restricted Stock Units [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			0.00%
Performance-based Restricted Stock Units [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Potential percentage of converted shares			200.00%
Restricted Stock Award [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period for sale or disposition			1 year
Restricted Stock Award [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award restriction period for sale or disposition			5 years
SWAP Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Elective deferrals vested percentage	100.00%		100.00%
Percentage of earnings deferred into company stock units	5.00%		5.00%
Percentage of earnings deferred into company stock units, Company match	25.00%		25.00%
Percentage of earnings deferred into company stock units, Additional elective deferral			1.00%
SWAP Plan [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			1 year
SWAP Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards vesting period in years			10 years

Off-Balance Sheet Credit Risk (

Off-Balance Sheet Credit Risk (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
General settlement period of securities transactions	2 days
Fair value of securities accepted as collateral permitted to sell or repledge	$ 2,700	$ 2,400
Fair value of collateral securities sold or repledged	495.5	233.7
Outstanding commitments to originate loans	205.7	160.2
Letters of credit outstanding	27.9	82.5
Unused Lines Of Credit [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Unused lines of credit to commercial and consumer borrowers	$ 769.5	$ 590.5
Standby Letters of Credit [Member] | Maximum [Member]
Fair Value Off Balance Sheet Risks Disclosure Information [Line Items]
Letters of credit, expiration period	1 year

Segment Reporting (Narrative) (

Segment Reporting (Narrative) (Details)	9 Months Ended
	Sep. 30, 2018Segment
Segment Reporting Information [Line Items]
Number of business segments	3
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Number of businesses within operating segment	2

Segment Reporting (Schedule Of

Segment Reporting (Schedule Of Operating Information, Segment) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Net revenues	[1]	$ 738,342	$ 721,169	$ 2,231,432	$ 2,122,347
Income/(loss) before income taxes		140,530	108,139	378,431	270,356
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	498,161	453,558	1,481,063	1,348,280
Income/(loss) before income taxes		183,377	161,756	548,043	457,045
Institutional Group [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	245,952	264,747	768,855	778,367
Income/(loss) before income taxes		34,305	51,717	114,899	144,481
Other [Member]
Segment Reporting Information [Line Items]
Net revenues	[1]	(5,771)	2,864	(18,486)	(4,300)
Income/(loss) before income taxes		$ (77,152)	$ (105,334)	$ (284,511)	$ (331,170)
[1]	No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2018 or 2017.

Segment Reporting (Schedule O_2

Segment Reporting (Schedule Of Operating Information, Segment) (Parenthetical) (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting [Abstract]
Net revenues accounted for by individual client, maximum percentage	10.00%	10.00%	10.00%	10.00%

Segment Reporting (Schedule O_3

Segment Reporting (Schedule Of Information Of Total Assets On Segment Basis) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total assets	$ 23,760,048	$ 21,383,953
Global Wealth Management [Member]
Segment Reporting Information [Line Items]
Total assets	19,874,154	17,717,617
Institutional Group [Member]
Segment Reporting Information [Line Items]
Total assets	3,511,720	3,313,304
Other [Member]
Segment Reporting Information [Line Items]
Total assets	$ 374,174	$ 353,032

Segment Reporting (Schedule O_4

Segment Reporting (Schedule Of Net Revenues Earned On Major Geographical Areas) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Total net revenues	[1]	$ 738,342	$ 721,169	$ 2,231,432	$ 2,122,347
United States [Member]
Segment Reporting Information [Line Items]
Total net revenues		703,746	680,505	2,113,039	2,017,999
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total net revenues		32,623	38,103	109,482	95,393
Other [Member]
Segment Reporting Information [Line Items]
Total net revenues		$ 1,973	$ 2,561	$ 8,911	$ 8,955
[1]	No individual client accounted for more than 10 percent of total net revenues for the three and nine months ended September 30, 2018 or 2017.

Earnings Per Share (Computation

Earnings Per Share (Computation Of Basic And Diluted Earnings Per Share ) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Net income	$ 103,858	$ 66,536	$ 279,906	$ 184,859
Preferred dividends	2,343	2,343	7,031	7,031
Net income available to common shareholders	$ 101,515	$ 64,193	$ 272,875	$ 177,828
Average shares used in basic computation	71,919	68,522	71,824	68,488
Dilutive effect of stock options and units	9,565	12,359	9,601	12,074
Average shares used in diluted computation	81,484	80,881	81,425	80,562
Basic	$ 1.41	$ 0.94	$ 3.80	$ 2.60
Diluted	$ 1.25	$ 0.79	$ 3.35	$ 2.21

Earnings Per Share (Details)

Earnings Per Share (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Cash dividend declared per common share	$ 0.12	$ 0.10	$ 0.36	$ 0.10
Cash dividend paid per common share	$ 0.12	$ 0.10	$ 0.36	$ 0.10

Shareholders' Equity (Details)

Shareholders' Equity (Details) - USD ($)	Aug. 31, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Number of shares authorized to be repurchased		6,000,000		6,000,000
Purchase of treasury stock		$ 16,600,000	$ 0	$ 62,500,000	$ 13,000,000
Treasury Stock, Shares, Acquired		300,000		1,100,000	300,000
Treasury Stock Acquired, Average Cost Per Share		$ 53.93		$ 55.66	$ 43.83
Business Bancshares, Inc. [Member]
Business Acquisition Equity Interests Issued Or Issuable [Line Items]
Shares issued				4,800,000
Common stock reissued				1,100,000
Stock issued for acquisition	2,000,000

Variable Interest Entities (Det

Variable Interest Entities (Details) $ in Millions	Sep. 30, 2018USD ($)
Variable Interest Entity [Line Items]
Assets in partnership	$ 233.4
Weisel Capital Management LLC [Member]
Variable Interest Entity [Line Items]
Assets in partnership	$ 285.5

Subsequent Events (Details)

Subsequent Events (Details)	9 Months Ended
	Sep. 30, 2018item
Subsequent Events [Abstract]
Number of types of subsequent events	2