Nature of Operations And Basis of Presentation	6 Months Ended
Jun. 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. 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 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 Bank & Trust (“Stifel Bank”). 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.

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.

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 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 Bank & Trust (“Stifel Bank”). 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.