Financial Statement Presentation	9 Months Ended
Sep. 30, 2018
Accounting Policies [Abstract]
Financial Statement Presentation	1. Financial Statement Presentation The Consolidated Financial Statements include the accounts of UMB Financial Corporation and its subsidiaries (collectively, the Company) after the elimination of all intercompany transactions. In the opinion of management of the Company, all adjustments relating to items that are of a normal recurring nature and necessary for a fair presentation of the financial position and results of operations have been made. The results of operations and cash flows for the interim periods presented may not be indicative of the results of the full year ending December 31, 2018. The financial statements should be read in conjunction with “Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations” within this Quarterly Report on Form 10-Q (the Form 10-Q) and in conjunction with the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the Securities and Exchange Commission (SEC) on February 22, 2018 (the Form 10-K). The Company is a financial holding company, which offers a wide range of banking and other financial services to its customers through its branches and offices. The Company’s national bank, UMB Bank, National Association (the Bank), has its principal office in Missouri and also has branches in Arizona, Colorado, Illinois, Kansas, Nebraska, Oklahoma, and Texas. The Company also has offices in Pennsylvania, South Dakota, Indiana, Utah, Minnesota, California, and Wisconsin. Until November 17, 2017, the Company owned Scout Investments, Inc. (Scout), an institutional asset-management company that offered domestic and international equity strategies. On November 17, 2017, the Company closed on the sale of Scout to Carillon Tower Advisers, Inc., a Florida corporation, for a purchase price of approximately $172.5 million, after giving effect to customary purchase price adjustments. In accordance with Accounting Standards Codification (ASC) Topic 205-20, Discontinued Operations, the results of Scout have been presented separately as (Loss) income from discontinued operations in the Company’s Consolidated Statements of Income.

1. Financial Statement Presentation

The Consolidated Financial Statements include the accounts of UMB Financial Corporation and its subsidiaries (collectively, the Company) after the elimination of all intercompany transactions. In the opinion of management of the Company, all adjustments relating to items that are of a normal recurring nature and necessary for a fair presentation of the financial position and results of operations have been made. The results of operations and cash flows for the interim periods presented may not be indicative of the results of the full year ending December 31, 2018. The financial statements should be read in conjunction with “Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations” within this Quarterly Report on Form 10-Q (the Form 10-Q) and in conjunction with the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the Securities and Exchange Commission (SEC) on February 22, 2018 (the Form 10-K).

The Company is a financial holding company, which offers a wide range of banking and other financial services to its customers through its branches and offices. The Company’s national bank, UMB Bank, National Association (the Bank), has its principal office in Missouri and also has branches in Arizona, Colorado, Illinois, Kansas, Nebraska, Oklahoma, and Texas. The Company also has offices in Pennsylvania, South Dakota, Indiana, Utah, Minnesota, California, and Wisconsin.

Until November 17, 2017, the Company owned Scout Investments, Inc. (Scout), an institutional asset-management company that offered domestic and international equity strategies. On November 17, 2017, the Company closed on the sale of Scout to Carillon Tower Advisers, Inc., a Florida corporation, for a purchase price of approximately $172.5 million, after giving effect to customary purchase price adjustments. In accordance with Accounting Standards Codification (ASC) Topic 205-20, Discontinued Operations, the results of Scout have been presented separately as (Loss) income from discontinued operations in the Company’s Consolidated Statements of Income.