Operations and Summary of Significant Accounting Policies Operations and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization And Nature Of Business	Organization and Nature of Business Texas Capital Bancshares, Inc. (“we,” “us”, or the “Company”), a Delaware corporation, was incorporated in November 1996 and commenced banking operations in December 1998. The consolidated financial statements of the Company include the accounts of the Company and its wholly owned subsidiary, Texas Capital Bank (the “Bank”). We serve the needs of commercial businesses and professionals and entrepreneurs located in Texas as well as operate several lines of business serving a regional or national clientele of commercial borrowers. We are primarily a secured lender, with the majority of our loans held for investment, excluding mortgage finance loans and other national lines of business, being made to businesses headquartered in or with operations in Texas. Our national lines of business provide specialized lending products to businesses throughout the United States. On September 6, 2022, we announced the sale of BankDirect Capital Finance (“BDCF” or “disposal group”), our insurance premium finance subsidiary, to AFCO Credit Corporation, an indirect wholly-owned subsidiary of Truist Financial Corp. The sale of BDCF includes its business operations and loan portfolio of approximately $3.1 billion as of September 30, 2022. The sale is an all-cash transaction for a purchase price of approximately $3.4 billion, representing an 8.5% asset premium compared to the value of the purchased loan portfolio as of September 30, 2022. The transaction resulted in the recognition of a disposal group that is classified as held for sale but does not meet the criteria for discontinued operations reporting. As such, the loans, assets and liabilities related to the disposal group were transferred at the lower of cost or fair value to loans held for sale, other assets held for sale and other liabilities held for sale, respectively, on the consolidated balance sheet as of September 30, 2022. The pre-tax net income for the disposal group for the three months ended September 30, 2022 and 2021 was $11.9 million and $17.4 million, respectively, and was $49.5 million and $48.7 million for the nine months ended September 30, 2022 and 2021, respectively. The sale is expected to close in the fourth quarter of 2022, subject to various customary closing conditions.
Basis of Accounting	Basis of Presentation Our accounting and reporting policies conform to accounting principles generally accepted in the United States (“GAAP”) and to generally accepted practices within the banking industry. Certain prior period balances have been reclassified to conform to the current period presentation. The consolidated interim financial statements are unaudited, and certain information and disclosures in the notes to consolidated unaudited financial statements that are presented in accordance with GAAP have been condensed or omitted. In the opinion of management, the interim financial statements include all normal and recurring adjustments and the disclosures made present a fair presentation of our financial position and results of operations. The consolidated financial statements have been prepared in accordance with GAAP for interim financial information and the instructions to Form 10-Q adopted by the U.S. Securities and Exchange Commission (“SEC”). Accordingly, the financial statements and the notes to the consolidated unaudited financial statements required by GAAP for complete annual financial statements do not include all of the information and should be read in conjunction with our consolidated financial statements, and notes thereto, for the year ended December 31, 2021, included in our Annual Report on Form 10-K for the year ended December 31, 2021 (the “2021 Form 10-K”). Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements. Actual results could differ from those estimates. The allowance for credit losses, the fair value of financial instruments and the status of contingencies are particularly susceptible to significant change.