Summary of Significant Accounting Policies (Policies)	9 Months Ended
Summary of Significant Accounting Policies (Policies)	Sep. 30, 2018
Accounting Policies [Abstract]
Nature of Operations	Nature of Operations Triumph Bancorp, Inc. (collectively with its subsidiaries, “Triumph”, or the “Company” as applicable) is a financial holding company headquartered in Dallas, Texas. The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries Triumph CRA Holdings, LLC (“TCRA”), TBK Bank, SSB (“TBK Bank”), TBK Bank’s wholly owned subsidiary Advance Business Capital LLC, which currently operates under the d/b/a of Triumph Business Capital (“TBC”), and TBK Bank’s wholly owned subsidiary Triumph Insurance Group, Inc. (“TIG”). On March 16, 2018, the Company sold the assets of Triumph Healthcare Finance (“THF”) and exited its healthcare asset based lending line of business. THF operated within the Company’s TBK Bank subsidiary. On March 31, 2017 the Company sold its membership interests in its wholly owned subsidiary Triumph Capital Advisors, LLC (“TCA”). See Note 2 – Business Combinations and Divestitures for details of the THF and TCA sales and their impact on our consolidated financial statements.
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements of the Company have been prepared in accordance with United States Generally Accepted Accounting Principles (“GAAP”) for interim financial information and in accordance with guidance provided by the Securities and Exchange Commission (“SEC”). Accordingly, the condensed financial statements do not include all of the information and footnotes required by GAAP for complete financial statements. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all normal and recurring adjustments considered necessary for a fair presentation. Transactions between the subsidiaries have been eliminated. These condensed consolidated financial statements should be read in conjunction with the Company’s Annual Report on Form 10-K for the year ended December 31, 2017. Operating results for the three and nine months ended September 30, 2018 are not necessarily indicative of the results that may be expected for the year ending December 31, 2018. The Company has three reportable segments consisting of Banking, Factoring, and Corporate. The Company’s Chief Executive Officer uses segment results to make operating and strategic decisions.
Revenue from Contracts with Customers	Revenue from Contracts with Customers The Company records revenue from contracts with customers in accordance with Accounting Standards Codification Topic 606, “Revenue from Contracts with Customers” (“Topic 606”). Under Topic 606, the Company must identify the contract with a customer, identify the performance obligations in the contract, determine the transaction price, allocate the transaction price to the performance obligations in the contract, and recognize revenue when (or as) the Company satisfies a performance obligation. Significant revenue has not been recognized in the current reporting period that results from performance obligations satisfied in previous periods. The Company’s primary sources of revenue are derived from interest and dividends earned on loans, investment securities, and other financial instruments that are not within the scope of Topic 606. The Company has evaluated the nature of its contracts with customers and determined that further disaggregation of revenue from contracts with customers into more granular categories beyond what is presented in the Consolidated Statements of Income was not necessary. The Company generally fully satisfies its performance obligations on its contracts with customers as services are rendered and the transaction prices are typically fixed; charged either on a periodic basis or based on activity. Because performance obligations are satisfied as services are rendered and the transaction prices are fixed, the Company has made no significant judgments in applying the revenue guidance prescribed in ASC 606 that affect the determination of the amount and timing of revenue from contracts with customers.
Income Taxes	Income Taxes On December 22, 2017, the United States enacted tax reform legislation commonly known as the Tax Cuts and Jobs Act (the “Tax Act”), resulting in significant modifications to existing law. Authoritative guidance and interpretation by regulatory bodies is ongoing, and as such, the accounting for the effects of the Tax Act is not final and the full impact of the new regulation is still being evaluated.
Adoption of New Accounting Standards	Adoption of New Accounting Standards In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, “Revenue from Contracts with Customers” (“ASU 2014-09”), which requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers. The ASU replaces most existing revenue recognition guidance in GAAP. The new standard was effective for the Company on January 1, 2018. Adoption of ASU 2014-09 did not have a material impact on the Company’s consolidated financial statements and related disclosures as the Company’s primary sources of revenues are derived from interest and dividends earned on loans, investment securities, and other financial instruments that are not within the scope of ASU 2014-09. The Company’s revenue recognition pattern for revenue streams within the scope of ASU 2014-09, including but not limited to service charges on deposit accounts and gains/losses on the sale of OREO, did not change significantly from current practice. The standard permits the use of either the full retrospective or modified retrospective transition method. The Company elected to use the modified retrospective transition method which requires application of ASU 2014-09 to uncompleted contracts at the date of adoption however, periods prior to the date of adoption will not be retrospectively revised as the impact of the ASU on uncompleted contracts at the date of adoption was not material. In January 2016, the FASB issued ASU No. 2016-01, “Financial Instruments – Overall: Recognition and Measurement of Financial Assets and Financial Liabilities” (“ASU 2016-01”). The guidance affects the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements of financial instruments. ASU 2016-01 was effective for the Company on January 1, 2018 and resulted in separate classification of equity securities previously included in available for sale securities on the consolidated balance sheets with changes in the fair value of the equity securities captured in the consolidated statements of income. See Note 3 – Securities for disclosures related to equity securities. Adoption of the standard also resulted in the use of an exit price rather than an entrance price to determine the fair value of loans not measured at fair value on a non-recurring basis in the consolidated balance sheets. See Note 10 – Fair Value Disclosures for further information regarding the valuation of these loans. In January 2017, the FASB issued ASU 2017-01, “Business Combinations (Topic 805): Clarifying the Definition of a Business,” (“ASU 2017-01”) to improve such definition and, as a result, assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of assets or as business combinations. The definition of a business impacts many areas of accounting including acquisitions, disposals, goodwill and consolidation. ASU 2017-01 was effective for the Company on January 1, 2018 and is to be applied under a prospective approach. The Company expects the adoption of this new guidance to impact the determination of whether future acquisitions are considered business combinations or asset purchases.
Newly Issued But Not Yet Effective Accounting Standards	Newly Issued, But Not Yet Effective Accounting Standards In February 2016, the FASB issued ASU 2016-02, “Leases (Topic 842)” (“ASU 2016-02”). The FASB issued this ASU to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet by lessees for those leases classified as operating leases under current U.S. GAAP and disclosing key information about leasing arrangements. The amendments in this ASU are effective for annual periods, and interim periods within those annual periods, beginning after December 15, 2018. Early application of this ASU is permitted for all entities. Adoption of ASU 2016-02 is not expected to have a material impact on the Company’s consolidated financial statements. The Company leases certain properties and equipment under operating leases that will result in the recognition of lease assets and lease liabilities on the Company’s balance sheet under the ASU, however, the majority of the Company’s properties and equipment are owned, not leased. At September 30, 2018, the Company had contractual operating lease commitments of approximately $21,863,000, before considering renewal options that are generally present. In June 2016, the FASB issued ASU 2016-13, “Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”). Among other things, ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions, and reasonable and supportable forecasts. Financial institutions and other organizations will now use forward-looking information to form their credit loss estimates. Many of the loss estimation techniques applied today will still be permitted, although the inputs to those techniques will change to reflect the full amount of expected credit losses. In addition, ASU 2016-13 amends the accounting for credit losses on debt securities and purchased financial assets with credit deterioration. The amendments in ASU 2016-13 are effective for fiscal years beginning after December 31, 2019, and interim periods within those years for public business entities that are SEC filers. Early adoption is permitted for fiscal years, and interim periods within those years, beginning after December 15, 2018, however, the Company does not currently plan to early adopt the ASU. The Company has assessed its data and system needs and is evaluating the impact that adoption of this standard will have on the financial condition and results of operations of the Company.

Disclosure of accounting policy for income taxes, which may include its accounting policies for recognizing and measuring deferred tax assets and liabilities and related valuation allowances, recognizing investment tax credits, operating loss carryforwards, tax credit carryforwards, and other carryforwards, methodologies for determining its effective income tax rate and the characterization of interest and penalties in the financial statements.