Texas Capital Bancshares (TCBI) 10-K 9 Feb 21 2020 FY Annual report Financial data

Cover Page

Cover Page - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Feb. 08, 2021	Jun. 30, 2020
Entity Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	001-34657
Entity Registrant Name	TEXAS CAPITAL BANCSHARES INC/TX
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	75-2679109
Entity Address, Address Line One	2000 McKinney Avenue
Entity Address, Address Line Two	Suite 700
Entity Address, City or Town	Dallas
Entity Address, State or Province	TX
Entity Address, Country	US
Entity Address, Postal Zip Code	75201
City Area Code	214
Local Phone Number	932-6600
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 1,546,867
Entity Common Stock, Shares Outstanding		50,473,827
Entity Central Index Key	0001077428
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Amendment Flag	false
Common Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	TCBI
Security Exchange Name	NASDAQ
Series A Preferred Stock [Member]
Entity Information [Line Items]
Title of 12(b) Security	6.5% Non-Cumulative Perpetual Preferred Stock Series A, par value $0.01 per share
Trading Symbol	TCBIP
Security Exchange Name	NASDAQ

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	Related Party TransactionsDuring 2020 and 2019, we have had transactions with our directors, executive officers and their affiliates and our employees. These transactions were made in the ordinary course of business and include extensions of credit and deposit transactions. The Bank had approximately $11.6 million in deposits from related parties, including directors, stockholders and their affiliates at December 31, 2020 and $13.0 million at December 31, 2019.

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Assets
Cash and due from banks	$ 173,573	$ 161,817
Interest-bearing deposits in other banks	9,032,807	4,233,766
Federal funds sold and securities purchased under resale agreements	0	30,000
Investment securities	3,196,970	239,871
Loans held for sale ($239.1 million and $2,571.3 million at December 2020 and 2019, respectively, at fair value)	283,165	2,577,134
Loans held for investment, mortgage finance	9,079,409	8,169,849
Loans held for investment (net of unearned income)	15,351,451	16,476,413
Less: Allowance for credit losses on loans	(254,615)	(195,047)
Loans held for investment, net	24,176,245	24,451,215
Mortgage servicing rights, net	105,424	64,904
Premises and equipment, net	24,546	31,212
Accrued interest receivable and other assets	715,699	740,051
Goodwill and intangible assets, net	17,667	18,099
Total assets	37,726,096	32,548,069
Deposits:
Non-interest-bearing	12,740,947	9,438,459
Interest-bearing	18,255,642	17,040,134
Total deposits	30,996,589	26,478,593
Accrued interest payable	$ 11,150	$ 12,760
Operating Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilities	us-gaap:OtherLiabilities
Other liabilities	$ 339,486	$ 318,094
Federal funds purchased and repurchase agreements	111,751	141,766
Other borrowings	3,000,000	2,400,000
Subordinated notes, net	282,490	282,129
Trust preferred subordinated debentures	113,406	113,406
Total liabilities	34,854,872	29,746,748
Comprehensive income:
Preferred stock, $.01 par value, $1,000 liquidation value: Authorized shares - 10,000,000; Issued shares - 6,000,000 shares issued at December 31, 2018 and 2017	150,000	150,000
Common stock, $.01 par value: Authorized shares - 100,000,000; Issued shares - 45,735,424 and 41,036,787 at December 31, 2018 and 2017, respectively	504	503
Additional paid-in capital	991,898	978,205
Retained earnings	1,713,056	1,663,671
Treasury stock (shares at cost: 417 at December 31, 2020 and 2019)	(8)	(8)
Accumulated other comprehensive income, net of taxes	15,774	8,950
Total stockholders’ equity	2,871,224	2,801,321
Total liabilities and stockholders’ equity	$ 37,726,096	$ 32,548,069

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Loans held for sale, fair value	$ 239,100,000	$ 2,571,300,000
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, Liquidation value	$ 1,000	$ 1,000
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	6,000,000	6,000,000
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	50,470,867	50,338,158
Treasury stock, shares	417	417

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME AND OTHER COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Interest income
Interest and fees on loans	$ 1,011,175	$ 1,284,036	$ 1,124,970
Investment securities	17,475	8,654	2,834
Federal funds sold and securities purchased under resale agreements	693	1,529	3,792
Interest-bearing deposits in other banks	27,569	71,093	32,597
Total interest income	1,056,912	1,365,312	1,164,193
Interest expense
Deposits	146,117	293,537	185,116
Federal funds purchased	1,083	11,872	6,531
Other borrowings	20,923	58,393	36,207
Subordinated notes	16,764	16,764	16,764
Trust preferred subordinated debentures	3,199	5,026	4,715
Total interest expense	188,086	385,592	249,333
Net interest income	868,826	979,720	914,860
Provision for credit losses	258,000	75,000	87,000
Net interest income after provision for credit losses	610,826	904,720	827,860
Non-interest income
Service charges on deposit accounts	11,620	11,320	12,787
Wealth management and trust fee income	9,998	8,810	8,148
Brokered loan fees	46,423	29,738	22,532
Servicing income	27,029	13,439	18,307
Swap fees	5,182	4,387	5,625
Net gain/(loss) on sale of loans held for sale	58,026	(20,259)	(15,934)
Other	27,238	45,005	26,559
Total non-interest income	185,516	92,440	78,024
Non-interest expense
Salaries and employee benefits	340,529	328,483	300,899
Net occupancy expense	34,955	32,989	30,342
Marketing	23,581	53,355	39,335
Legal and professional	52,132	52,460	42,990
Communications and technology	103,054	44,826	30,056
FDIC insurance assessment	25,955	20,093	24,307
Servicing-related expenses	64,625	22,573	14,934
Merger-related expenses	17,756	1,370	0
Other	41,809	44,701	49,670
Total non-interest expense	704,396	600,850	532,533
Income before income taxes	91,946	396,310	373,351
Income tax expense	25,657	84,295	79,964
Net income	66,289	312,015	293,387
Preferred stock dividends	(9,750)	(9,750)	(9,750)
Net income available to common stockholders	56,539	302,265	283,637
Other comprehensive income
Change in unrealized gain (loss) on available-for-sale debt securities arising during period, before tax	8,639	10,674	7
Income tax expense/(benefit)	1,815	2,242	1
Other comprehensive income, net of tax	6,824	8,432	6
Comprehensive income	$ 73,113	$ 320,447	$ 293,393
Basic earnings per common share
Basic earnings per common share	$ 1.12	$ 6.01	$ 5.68
Diluted earnings per common share
Diluted earnings per common share	$ 1.12	$ 5.99	$ 5.64

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment		Preferred Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained EarningsCumulative Effect, Period of Adoption, Adjustment		Treasury Stock	Accumulated Other Comprehensive Income	Accumulated Other Comprehensive IncomeCumulative Effect, Period of Adoption, Adjustment
Beginning balance at Dec. 31, 2016	$ 1,997,890
Comprehensive income:
Net income/(loss)	196,081
Comprehensive income	196,094
Ending balance (in shares) at Dec. 31, 2017				6,000,000	49,643,761					417
Ending balance at Dec. 31, 2017	2,190,072	$ 2	[1]	$ 150,000	$ 496	$ 961,305	$ 1,077,851	$ (82)	[1]	$ (8)	$ 428	$ 84	[1]
Comprehensive income:
Net income/(loss)	293,387						293,387
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	6										6
Comprehensive income	293,393
Stock-based compensation expense recognized in earnings	8,973					8,973
Preferred stock dividends	(9,750)						(9,750)
Issuance of stock related to stock-based awards (in shares)					120,242
Issuance of stock related to stock-based awards	(2,382)				$ 1	(2,383)
Issuance of common stock related to warrants (in shares)					437,124
Issuance of common stock related to warrants	0				$ 5	(5)
Ending balance (in shares) at Dec. 31, 2018				6,000,000	50,201,127					417
Ending balance at Dec. 31, 2018	2,480,308			$ 150,000	$ 502	967,890	1,361,406			$ (8)	518
Comprehensive income:
Net income/(loss)	312,015						312,015
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	8,432										8,432
Comprehensive income	320,447
Stock-based compensation expense recognized in earnings	11,775					11,775
Preferred stock dividends	(9,750)						(9,750)
Issuance of stock related to stock-based awards (in shares)					128,263
Issuance of stock related to stock-based awards	(1,459)				$ 1	(1,460)
Issuance of common stock related to warrants (in shares)					8,768
Issuance of common stock related to warrants	0				$ 0	0
Ending balance (in shares) at Dec. 31, 2019				6,000,000	50,338,158					417
Ending balance at Dec. 31, 2019	2,801,321	$ (7,154)	[2]	$ 150,000	$ 503	978,205	1,663,671	$ (7,154)	[2]	$ (8)	8,950	$ 0	[2]
Comprehensive income:
Net income/(loss)	66,289						66,289
Change in unrealized gain (loss) on available-for-sale securities, net of taxes	6,824										6,824
Comprehensive income	73,113
Stock-based compensation expense recognized in earnings	15,681					15,681
Preferred stock dividends	(9,750)						(9,750)
Issuance of stock related to stock-based awards (in shares)					132,709
Issuance of stock related to stock-based awards	(1,987)				$ 1	(1,988)
Ending balance (in shares) at Dec. 31, 2020				6,000,000	50,470,867					417
Ending balance at Dec. 31, 2020	$ 2,871,224			$ 150,000	$ 504	$ 991,898	$ 1,713,056			$ (8)	$ 15,774
[1]	Represents the impact of adopting Accounting Standard Update ("ASU") 2018-02 and ASU 2016-01. See Note 1 to the consolidated financial statements for more information.
[2]	Represents the impact of adopting ASU 2016-13. See Note 1 to the consolidated financial statements for more information.

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net income	$ 60,176	$ (16,687)	$ 64,420	$ 81,701	$ 66,289	$ 312,015	$ 293,387	$ 196,081
Adjustments to reconcile net income to net cash provided by/(used in) operating activities:
Provision for credit losses	32,000	96,000	17,000	20,000	258,000	75,000	87,000
Deferred tax expense (benefit)					(7,964)	10,796	(6,400)
Depreciation and amortization					74,925	37,267	32,022
Net (gain)/loss on sale of loans held for sale					(58,026)	20,259	15,934
Increase (decrease) in valuation allowance on mortgage servicing rights					20,164	5,803	(2,823)
Stock-based compensation expense					17,441	17,604	16,938
Purchases and originations of loans held for sale					(11,366,986)	(10,183,057)	(6,753,709)
Proceeds from sales and repayments of loans held for sale					13,619,623	9,508,927	5,759,067
Changes in operating assets and liabilities:
Accrued interest receivable and other assets					10,654	(143,617)	(123,542)
Accrued interest payable and other liabilities					5,749	98,735	2,411
Net cash provided by/(used in) operating activities					2,639,869	(240,268)	(679,715)
Investing activities
Purchases of investment securities					(3,001,746)	(113,233)	(101,558)
Maturities and calls of available-for-sale securities					0	0	0
Principal payments received on investment securities					52,609	6,185	3,426
Originations of mortgage finance loans					(216,234,122)	(138,759,289)	(99,151,237)
Proceeds from pay-offs of mortgage finance loans					215,324,562	136,466,964	98,581,873
Net (increase)/decrease in loans held for investment, excluding mortgage finance loans					926,176	139,868	(1,402,068)
Purchase of premises and equipment, net					(2,796)	(16,651)	(7,651)
Proceeds from sale of MSRs					0	0	70,824
Proceeds from sale of other real estate owned, net					0	79	13,645
Net cash used in investing activities					(2,935,317)	(2,276,077)	(1,992,746)
Financing activities
Net increase in deposits					4,517,996	5,872,480	1,482,933
Costs from issuance of stock related to stock-based awards and warrants					(1,986)	(1,459)	(2,382)
Preferred dividends paid					(9,750)	(9,750)	(9,750)
Net increase/(decrease) in other borrowings						(1,500,000)
Net increase/(decrease) in other borrowings					600,000		1,100,000
Net increase/(decrease) in federal funds purchased and repurchase agreements					(30,015)	(499,408)	276,134
Net cash provided by financing activities					5,076,245	3,861,863	2,846,935
Net increase in cash and cash equivalents					4,780,797	1,345,518	174,474
Cash and cash equivalents at beginning of period		$ 4,425,583		$ 3,080,065	4,425,583	3,080,065	2,905,591
Cash and cash equivalents at end of period	$ 9,206,380		$ 4,425,583		9,206,380	4,425,583	3,080,065	$ 2,905,591
Supplemental disclosures of cash flow information:
Cash paid during the period for interest					189,696	393,507	236,338
Cash paid during the period for income taxes					$ 26,152	$ 89,967	$ 75,405

Operations and Summary of Signi

Operations and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Operations and Summary of Significant Accounting Policies	Operations and Summary of Significant Accounting Policies Organization and Nature of Business Texas Capital Bancshares, Inc. (the "Company” or "TCBI"), 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 Texas Capital Bancshares, Inc. and its wholly owned subsidiary, Texas Capital Bank, National Association (the "Bank”). We serve the needs of commercial businesses and successful 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 or with operations in Texas. Our national lines of business provide specialized leading products to businesses throughout the United States. On December 9, 2019, the Company and IBTX entered into the Merger Agreement, pursuant to which, on the terms and subject to the conditions therein, the Company would be merged with and into IBTX. On May 22, 2020, the Company and IBTX entered into an agreement pursuant to which the parties mutually agreed to terminate the Merger Agreement. Neither party paid a termination fee in connection with the termination of the Merger Agreement. 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. Revision of Prior Period Financial Statements During the second quarter of 2020, the Company identified an error in our historical financial statements related to the accounting for certain share-based liabilities of a consolidated entity that contained put features, whereby the liabilities were not remeasured to their puttable value at each period end. The aggregate amount of the errors at each period end represented 1% or less of our stockholders' equity in all prior periods. In accordance with the guidance set forth in SEC Staff Bulletin 99, Materiality , and SEC Staff Accounting Bulletin 108, Considering the Effects of Prior Year Misstatements when Quantifying Misstatements in Current Year Financials , the Company concluded that the error was not material, individually or in the aggregate with other previously identified immaterial errors, to any prior periods, the current period or the trend in earnings from a quantitative and qualitative perspective. However, correcting the cumulative effect of the errors in the current period would have resulted in a material misstatement in the current period and, as such, we have revised our previously reported financial information contained in our Annual Report on Form 10-K for the year ended December 31, 2019 to correct the immaterial error, as well as other previously identified immaterial errors. A summary of revisions to certain previously reported financial information is presented below: Revised Consolidated Balance Sheets December 31, 2019 December 31, 2018 December 31, 2017 ( in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Other liabilities $ 287,157 $ 30,937 $ 318,094 $ 194,238 $ 20,086 $ 214,324 $ 182,212 $ 12,649 $ 194,861 Total liabilities 29,715,811 30,937 29,746,748 25,757,373 20,086 $ 25,777,459 22,872,924 12,649 22,885,573 Retained Earnings 1,694,608 (30,937) 1,663,671 1,381,492 (20,086) $ 1,361,406 1,090,500 (12,649) 1,077,851 Total Equity 2,832,258 (30,937) 2,801,321 2,500,394 (20,086) $ 2,480,308 2,202,721 (12,649) 2,190,072 Revised Consolidated Statement of Income and Other Comprehensive Income Year Ended December 31, 2019 Year Ended December 31, 2018 Year Ended December 31, 2017 (in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Salaries and employee benefits expense $ 315,080 $ 13,403 $ 328,483 $ 291,768 $ 9,131 $ 300,899 $ 264,231 $ 2,230 $ 266,461 Other non-interest expense 47,253 (2,552) 44,701 51,364 (1,694) 49,670 49,296 (1,248) 48,048 Total non-interest expense 589,999 10,851 600,850 525,096 7,437 532,533 465,876 982 466,858 Income before tax 407,161 (10,851) 396,310 380,788 (7,437) 373,351 325,708 (982) 324,726 Net income 322,866 (10,851) 312,015 300,824 (7,437) 293,387 197,063 (982) 196,081 Net income available to common stockholders 313,116 (10,851) 302,265 291,074 (7,437) 283,637 187,313 (982) 186,331 Comprehensive income 331,298 (10,851) 320,447 300,830 (7,437) 293,393 197,076 (982) 196,094 Revised Consolidated Statement of Stockholders' Equity Year Ended December 31, 2019 Year Ended December 31, 2018 Year Ended December 31, 2017 (in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Beginning balance retained earnings $ 1,381,492 $ (20,086) $ 1,361,406 $ 1,090,500 $ (12,649) $ 1,077,851 $ 903,187 $ (11,667) $ 891,520 Beginning balance total equity 2,500,394 (20,086) 2,480,308 2,202,721 (12,649) 2,190,072 2,009,557 (11,667) 1,997,890 Ending balance retained earnings 1,694,608 (30,937) 1,663,671 1,381,492 (20,086) 1,361,406 1,090,500 (12,649) 1,077,851 Ending balance total equity 2,832,258 (30,937) 2,801,321 2,500,394 (20,086) 2,480,308 2,202,721 (12,649) 2,190,072 The share-based liabilities relate to agreements with certain employees of a subsidiary of the Company that was acquired in 2005. The terms of the agreements include a put feature that, when exercised, requires mandatory settlement by the Company of the share-based liability at a formulaic price. The put feature causes the liability to be remeasured to current puttable value at each period end. The impact of adjusting the liability to puttable value at each period end is recorded in salaries and employee benefits expense. During the second quarter of 2020, put features were exercised on a portion of the outstanding liability. As of December 31, 2020, the carrying value of these share-based liabilities totaled $7.8 million and is recorded in other liabilities on the consolidated balance sheets. Accounting Changes On January 1, 2020, we adopted ASU 2016-13 "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments" ("ASU 2016-13"), which replaces the incurred loss methodology for determining our provision for credit losses and allowance for credit losses with an expected loss methodology that is referred to as the Current Expected Credit Loss ("CECL") model. The measurement of expected credit losses under the CECL methodology is applicable to financial assets measured at amortized cost, including loan receivables and held-to-maturity debt securities. It also applies to off-balance sheet credit exposures not accounted for as insurance (loan commitments, standby letters of credit, financial guarantees, and other similar instruments) and net investments in leases recognized by a lessor in accordance with ASU 2016-02 "Leases (Topic 842)" . In addition, ASU 2016-13 made changes to the accounting for available-for-sale debt securities. One such change is to require credit-related impairments to be recognized in the allowance for credit losses rather than as a write-down of the securities' amortized cost basis when management does not intend to sell or believes that it is not more likely than not that they will be required to sell the securities prior to recovery of the securities amortized cost basis. We adopted ASU 2016-13 using the modified retrospective method for all financial assets measured at amortized cost, off-balance sheet credit exposures and net investments in leases. Results for reporting periods beginning after January 1, 2020 are presented under ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. Our accounting policies changed significantly upon the adoption of CECL on January 1, 2020. Prior to January 1, 2020, the allowance for loan losses was based on incurred credit losses in accordance with accounting policies disclosed in Note 1 - Operations and Summary of Significant Accounting Policies in the accompanying notes to the consolidated financial statements included in our Annual Report on Form 10-K for the year-ended December 31, 2019. We adopted ASU 2016-13 using the prospective transition approach for debt securities for which other-than-temporary impairment had been recognized prior to January 1, 2020. As a result, the amortized cost basis remains the same before and after the effective date of ASU 2016-13. The following table illustrates the impact of adopting ASU 2016-13 and details how outstanding loan balances have been reclassified as a result of changes made to our primary portfolio segments under CECL: January 1, 2020 (in thousands) As Reported Under ASU 2016-13 Pre-ASU 2016-13 Impact of ASU 2016-13 Adoption Assets: Loans held for investment (outstanding balance) Commercial $ 9,133,444 $ 10,230,828 $ (1,097,384) Energy 1,425,309 1,425,309 Mortgage finance 8,169,849 8,169,849 — Construction 2,563,339 (2,563,339) Real estate 6,008,040 3,444,701 2,563,339 Consumer 71,463 (71,463) Equipment leases 256,462 (256,462) Allowance for credit losses on loans (203,632) (195,047) (8,585) Total loans held for investment, net 24,442,630 24,451,215 (8,585) Net deferred tax asset 23,058 21,064 1,994 Liabilities: Allowance for credit losses on off-balance sheet exposures 9,203 8,640 563 Equity: Retained earnings 1,656,517 1,663,671 (7,154) In connection with our adoption of ASU 2016-13, changes were made to our primary portfolio segments to align with the methodology applied in determining the allowance under CECL. These changes included segregating energy loans into a stand-alone portfolio segment and reclassifying consumer and equipment leases into the commercial loan portfolio segment. Additionally, construction and real estate loans were combined into a single portfolio segment, referred to as real estate. The real estate loan portfolio segment includes loans further categorized as commercial real estate, residential homebuilder finance, secured by 1-4 family and an "other" category. See Allowance for Credit Losses below for further discussion of these portfolio segments. 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. Basic and Diluted Earnings Per Common Share Basic earnings per common share is based on net income available to common stockholders divided by the weighted-average number of common shares outstanding during the period excluding non-vested stock. Diluted earnings per common share include the dilutive effect of non-vested stock-based awards granted using the treasury stock method. A reconciliation of the weighted-average shares used in calculating basic earnings per common share and the weighted average common shares used in calculating diluted earnings per common share for the reported periods is provided in Note 2 — Earnings Per Share. Accumulated Other Comprehensive Income Unrealized gains or losses on our available-for-sale debt securities (after applicable income tax expense or benefit) are included in accumulated other comprehensive income (loss), net ("AOCI"). AOCI is reported in the accompanying consolidated statements of stockholders’ equity and consolidated statements of income and other comprehensive income. GAAP does not permit the adjustment of tax amounts in AOCI for changes in tax rates; as a result the effects become "stranded" in AOCI. Stranded tax effects caused by the 2018 revaluation of deferred taxes resulting from the corporate tax rates established by the Tax Cuts and Jobs Act (the "Tax Act") are reclassified from AOCI to retained earnings in accordance with our early adoption of ASU 2018-02 " Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income." Cash and Cash Equivalents Cash equivalents include amounts due from banks, interest-bearing deposits in other banks, federal funds sold and securities purchased under resale agreements. Investment Securities Investment securities include debt securities and equity securities at fair value. Debt Securities Debt securities are classified as trading, available-for-sale or held-to-maturity. Management classifies securities at the time of purchase and re-assesses such designation at each balance sheet date; however, transfers between categories from this re-assessment are rare. All debt securities are available-for-sale as of December 31, 2020 and 2019. Trading Account Debt securities acquired for resale in anticipation of short-term market movements are classified as trading, with realized and unrealized gains and losses recognized in income. Held-to-Maturity Debt securities are classified as held-to-maturity when we have the positive intent and ability to hold the securities to maturity. Held-to-maturity securities are stated at amortized cost. Debt securities not classified as held-to-maturity or trading are classified as available-for-sale. Available-for-Sale Available-for-sale debt securities are stated at fair value. Unrealized gains are reported as a separate component of AOCI, net of tax. For available-for-sale debt securities in an unrealized loss position, we first assess whether we intend to sell, or it is more-likely-than-not that we will be required to sell, the securities before recovery of the amortized cost basis. If either of these criteria is met, the securities' amortized cost basis is written down to fair value as a current period expense. If either of the above criteria is not met, we evaluate whether the decline in fair value is the result of credit losses or other factors. In making this assessment, we may consider various factors including the extent to which fair value is less than amortized cost, performance of any underlying collateral and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected are compared to the amortized cost basis of the security and any excess of the amortized cost basis over the present value of expected cash flows is recorded as an allowance for credit loss, limited to the amount by which the fair value is less than the amortized cost basis. Any impairment not recorded through an allowance for credit loss is recognized in AOCI, net of tax, as a non credit-related impairment. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security. Such amortization and accretion are included in interest income from securities. Realized gains and losses and declines in value judged to be other-than-temporary are included in gain (loss) on sale of securities. The cost of securities sold is based on the specific identification method. We have made a policy election to exclude accrued interest from the amortized cost basis of available-for-sale debt securities and report accrued interest separately in accrued interest and other assets in the consolidated balance sheets. Available-for-sale debt securities are placed on non-accrual status when we no longer expect to receive all contractual amounts due, which is generally at 90 days past due. Accrued interest receivable is reversed against interest income when a security is placed on non-accrual status. Accordingly, we do not recognize an allowance for credit loss against accrued interest receivable. Included in debt securities available-for-sale are Credit Risk Transfer ("CRT") securities. CRT securities represent unsecured obligations issued by government sponsored entities ("GSEs") such as Freddie Mac and are designed to transfer mortgage credit risk from the GSE to private investors. CRT securities are structured to be subject to the performance of a reference pool of mortgage loans in which we share in 50% of the first losses with the GSE. If the reference pool incurs losses, the amount we will recover on the notes is reduced by our share of the amount of such losses, which could potentially be up to 100% of the amount outstanding. Unrealized losses recognized in AOCI for the CRT securities are primarily related to the difference between the current market rate for similar securities and the stated interest rate and are not considered to be related to credit loss events. The CRT securities are generally interest-only for an initial period of time and may be restricted from being transferred until a future date. Equity Securities Beginning January 1, 2018, upon adoption of ASU 2016-01 " Recognition and Measurement of Financial Assets and Financial Liabilities," equity securities with readily determinable fair values are stated at fair value with realized and unrealized gains and losses reported in income. For periods prior to January 1, 2018, equity securities were classified as available-for-sale and stated at fair value with unrealized gains and losses reported as a separate component of AOCI, net of tax. Equity securities without readily determinable fair values are recorded at cost less any impairment, if any. Loans Loans Held for Sale Through our mortgage correspondent aggregation ("MCA") program, we commit to purchase residential mortgage loans from independent correspondent lenders and deliver those loans into the secondary market via whole loan sales to independent third parties or in securitization transactions to third parties such as Ginnie Mae or to government sponsored entities such as Fannie Mae or Freddie Mac ("GSEs"). In some cases, we retain the mortgage servicing rights. Once purchased, these loans are classified as held for sale and are carried at fair value pursuant to our election of the fair value option in accordance with Accounting Standards Codification ("ASC") 825, Financial Instruments . At the commitment date, we enter into a corresponding forward sale commitment with a third party, typically Ginnie Mae or a GSE, to deliver the loans within a specified timeframe. The estimated gain/loss for the entire transaction (from initial purchase commitment to final delivery of loans) is recorded as an asset or liability. The fair value of loans held for sale is derived from observable current market prices, when available, and includes the fair value of the mortgage servicing rights. Adjustments to reflect unrealized gains and losses resulting from changes in fair value and realized gains and losses upon ultimate sale of the loans are classified as gain/(loss) on sale of loans held for sale in the consolidated statements of income and other comprehensive income. Residential mortgage loans held for sale are subject to both credit and interest rate risk. Credit risk is managed through underwriting policies and procedures, including collateral requirements, which are generally accepted by the secondary loan markets. Exposure to interest rate fluctuations is partially managed through forward sales contracts, which set the price for loans that will be delivered in the next 60 to 90 days. Pursuant to Ginnie Mae servicing guidelines, we have the unilateral right, but not the obligation, to repurchase certain delinquent loans securitized in Ginnie Mae pools, if they meet defined delinquent loan criteria. Once the delinquency criteria have been met, and regardless of whether the repurchase option has been exercised, we account for these loans as if they had been repurchased and recognize the loans and a corresponding liability as held for sale and other liabilities, respectively, in the consolidated balance sheets. If the loans are actually repurchased, the liability is extinguished and the loans continue to be reported as held for sale. As a Ginnie Mae approved lender, we may recover losses incurred on repurchased loans through a claims process with the government agency. From time to time we hold for sale the guaranteed portion of Small Business Administration 7(a) loans, which are carried at lower of cost or market. Loans Held for Investment Loans held for investment (including financing leases) are stated at the amount of unpaid principal reduced by deferred income (net of costs). Interest on loans is recognized using the simple interest method on the daily balances of the principal amounts outstanding. Loan origination fees, net of direct loan origination costs, and commitment fees are deferred and amortized as an adjustment to yield over the life of the loan, or over the commitment period, as applicable. Restructured loans are loans on which, due to the borrower’s financial difficulties, we have granted a concession that we would not otherwise consider for borrowers of similar credit quality. This may include a transfer of real estate or other assets from the borrower, a modification of loan terms, or a combination of the two. Modifications of terms that could potentially qualify as a restructuring include reduction of contractual interest rate, extension of the maturity date at a contractual interest rate lower than the current rate for new debt with similar risk, a reduction of the face amount of debt or forgiveness of either principal or accrued interest. A loan continues to qualify as restructured until a consistent payment history or change in the borrower’s financial condition has been evidenced, generally for no less than twelve months. If the restructuring agreement specifies an interest rate at the time of the restructuring that is greater than or equal to the rate that we are willing to accept for a new extension of credit with comparable risk, then the loan is no longer considered a restructuring if it is in compliance with the modified terms in calendar years after the year of the restructure. A loan is considered past due when a contractually due payment has not been received by the contractual due date. We place a loan on non-accrual when there is a clear indication that the borrower’s cash flow may not be sufficient to meet payments as they become due, which is generally when a loan is 90 days past due. When a loan is placed on non-accrual status, all previously accrued and unpaid interest is reversed as a reduction of current period interest income. Interest income is subsequently recognized on a cash basis as long as the remaining book balance of the asset is deemed to be collectible. If collectability is questionable, then cash payments are applied to principal. A loan is placed back on accrual status when both principal and interest are current and it is probable that we will be able to collect all amounts due (both principal and interest) according to the terms of the loan agreement. Loans held for investment includes legal ownership interests in mortgage loans that we purchase through our mortgage warehouse lending division. The ownership interests are purchased from unaffiliated mortgage originators who are seeking additional funding through sale of the undivided ownership interests to facilitate their ability to originate loans. The mortgage originator has no obligation to offer and we have no obligation to purchase these interests. The originator closes mortgage loans consistent with underwriting standards established by approved investors, and, at the time of the sale to the investor, our ownership interest and that of the originator are delivered by us to the investor selected by the originator and approved by us. We typically purchase up to a 99% ownership interest in each mortgage with the originator owning the remaining percentage. These mortgage ownership interests are generally held by us for a period of less than 30 days and more typically 10-20 days. Because of conditions in agreements with originators designed to reduce transaction risks, under ASC 860, Transfers and Servicing of Financial Assets (“ASC 860”), the ownership interests do not qualify as participating interests. Under ASC 860, the ownership interests are deemed to be loans to the originators and payments we receive from investors are deemed to be payments made by or on behalf of the originator to repay the loan deemed made to the originator. Because we have an actual, legal ownership interest in the underlying residential mortgage loan, these interests are reported as extensions of credit to the originators that are secured by the mortgage loans as collateral. Due to market conditions or events of default by the investor or the originator, we could be required to purchase the remaining interests in the mortgage loans and hold them beyond the expected 10-20 days. Mortgage loans acquired under these conditions would require mark-to-market adjustments to income and could require further allocations of the allowance for credit losses or be subject to charge-off in the event the loans become impaired. Allowance for Credit Losses The allowance for credit losses is an estimate of the expected credit losses in the loans held for investment and available-for-sale debt securities portfolio. The following is our discussion of the allowance for credit losses on loans held for investment. See "Investment Securities - Available-for-Sale" above for discussion of the allowance for credit losses on available-for-sale debt securities. ASU 2016-13 replaces the incurred loss impairment model, which recognizes losses when it becomes probable that a credit loss will be incurred, with a requirement to recognize lifetime expected credit losses immediately when a financial asset is originated or purchased. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of loans to present the net amount expected to be collected on the loans. Loans, or portions thereof, are charged off against the allowance when they are deemed uncollectible. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Management estimates the allowance balance using relevant available information, from internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. Adjustments to historical loss information are made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, credit quality, or term, as well as for changes in macroeconomic conditions, such as changes in unemployment rates, crude oil prices, property values or other relevant factors. The allowance for credit losses is comprised of reserves measured on a collective (pool) basis based on a lifetime loss-rate model when similar risk characteristics exist. Reserves on loans that do not share risk characteristics are evaluated on an individual basis. In order to determine the allowance for credit losses, all loans are assigned a credit grade. Loans graded substandard or worse and greater than $500,000 are specifically reviewed for loss potential and when deemed appropriate are assigned a reserve based on an individual evaluation. For purposes of determining the pool-basis reserve, the remainder of the portfolio, representing all loans not assigned an individual reserve, is segregated first by portfolio segment, then by product type, to recognize differing risk profiles within portfolio segments, and finally by credit grade. Each credit grade within each product type is assigned a historical loss rate. These historical loss rates are then modified to incorporate our reasonable and supportable forecast of future losses at the portfolio segment level, as well as any necessary qualitative adjustments using a Portfolio Level Qualitative Factor ("PLQF") and/or a Portfolio Segment Level Qualitative Factor ("SLQF"). These modified historical loss rates are multiplied by the outstanding principal balance of each loan to calculate a required reserve. A similar process is employed to calculate a reserve assigned to off-balance sheet commitments, specifically unfunded loan commitments and letters of credit, and any needed reserve is recorded in other liabilities. The PLQF and SLQF are utilized to address factors that are not present in historical loss rates and are otherwise unaccounted for in the quantitative process. The PLQF is used to apply a qualitative adjustment across the entire portfolio of loans, while the SLQF is designed to apply a qualitative adjustment across a single portfolio segment. Even though portions of the allowance may be allocated to specific loans, the entire allowance is available for any credit that, in management’s judgment, should be charged off. We generally use a two-year forecast period, based on a single consensus forecast scenario, using variables we believe are most relevant to each portfolio segment. For periods beyond which we are able to develop reasonable and supportable forecasts, we immediately revert to the average historical loss rate. The forecast period and scenario used is reviewed on a quarterly basis and may be adjusted based on management's view of the current economic conditions and level of predictability the forecast can provide. Portfolio segments are used to pool loans with similar risk characteristics and align with our methodology for measuring expected credit losses. A summary of our primary portfolio segments is as follows: Commercial . Our commercial loan portfolio is comprised of lines of credit for working capital, term loans and leases to finance equipment and other business assets across a variety of industries. These loans are used for general corporate purposes including financing working capital, internal growth, acquisitions and business insurance premiums and are generally secured by accounts receivable, inventory, equipment and other assets of our clients’ businesses. Our commercial loan portfolio also includes consumer loans because our small portfolio of consumer loans is largely comprised of accommodation loans to individuals associated with our commercial clients. Energy . Our energy loan portfolio is primarily comprised of loans to exploration and production (“E&P”) companies that are generally collateralized with proven reserves based on appropriate valuation standards that take into account the risk of oil and gas price volatility. The majority of this portfolio is first lien, senior secured, reserve-based lending, which we believe is the lowest-risk form of energy lending. Energy loans are impacted by commodity price volatility, as well as changes in consumer and business demand. Mortgage finance . Mortgage finance loans relate to our mortgage warehouse lending operations in which we purchase mortgage loan ownership interests from unaffiliated mortgage originators that are generally held by us for a period of less than 30 days and more typically 10-20 days before they are sold to an approved investor. Volumes fluctuate based on the level of market demand for the product and the number of days between purchase and sale of the loans, which can be affected by changes in overall market interest rates and housing demand and tend to peak at the end of each month. Mortgage finance loans are consistently underwritten based on standards established by the approved investors. Market conditions or events of default by an investor or originator could require that we repurchase the remaining interests in the mortgage loans and hold them beyond the expected 10-20 days. Real estate . Our real estate portfolio is comprised of the following types of loans: Commercial real estate ("CRE") . Our CRE portfolio is comprised of both construction/development financing and limited term financing provided to professional real estate developers and owners/managers of commercial real estate projects and properties who have a demonstrated record of past success with similar properties. Collateral properties include office buildings, warehou

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table presents the computation of basic and diluted earnings per share: Year ended December 31, (in thousands except per share data) 2020 2019 2018 Numerator: Net income $ 66,289 $ 312,015 $ 293,387 Preferred stock dividends 9,750 9,750 9,750 Net income available to common stockholders $ 56,539 $ 302,265 $ 283,637 Denominator: Denominator for basic earnings per share—weighted average shares 50,430,326 50,286,300 49,936,702 Effect of employee stock-based awards(1) 152,653 132,904 218,275 Effect of warrants to purchase common stock — — 117,895 Denominator for dilutive earnings per share—adjusted weighted average shares and assumed conversions 50,582,979 50,419,204 50,272,872 Basic earnings per common share $ 1.12 $ 6.01 $ 5.68 Diluted earnings per common share $ 1.12 $ 5.99 $ 5.64 (1) SARs and RSUs outstanding of 453,024, 86,308 and 27,100 in 2020, 2019 and 2018, respectively, have not been included in diluted earnings per share because to do so would have been antidilutive for the periods presented.

Investment Securities

Investment Securities	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Investment Securities	Investment Securities Available-for-Sale Debt Securities The following is a summary of available-for-sale debt securities: (in thousands) Amortized Gross Gross Estimated December 31, 2020 U.S. government agency securities $ 125,000 $ 1 $ (1,412) $ 123,589 Residential mortgage-backed securities 2,818,518 11,566 (1,128) 2,828,956 Tax-exempt asset-backed securities 184,940 14,236 — 199,176 Credit risk transfer securities 14,713 — (3,296) 11,417 Total $ 3,143,171 $ 25,803 $ (5,836) $ 3,163,138 December 31, 2019 Residential mortgage-backed securities $ 4,991 $ 275 $ — $ 5,266 Tax-exempt asset-backed securities 183,225 13,802 — 197,027 Credit risk asset-backed securities 14,713 — (2,749) 11,964 Total $ 202,929 $ 14,077 $ (2,749) $ 214,257 (1) Excludes accrued interest receivable of $6.0 million and $1.6 million at December 31, 2020 and 2019, respectively, that is recorded in accrued interest receivable and other assets. The amortized cost and estimated fair value, excluding accrued interest receivable, and weighted average yield of available-for-sale debt securities are presented below by contractual maturity: (in thousands, except percentage data) Less Than After One After Five After Ten Total December 31, 2020 U.S. government agency securities:(1) Amortized cost $ — $ — $ 125,000 $ — $ 125,000 Estimated fair value — — 123,589 — 123,589 Weighted average yield(3) — % — % 1.13 % — % 1.13 % Residential mortgage-backed securities:(1) Amortized cost $ — $ 545 $ 17,500 $ 2,800,473 $ 2,818,518 Estimated fair value — 605 17,490 2,810,861 2,828,956 Weighted average yield(3) — % 4.58 % 1.08 % 1.25 % 1.25 % Tax-exempt asset-backed securities:(1) Amortized Cost — — — 184,940 184,940 Estimated fair value — — — 199,176 199,176 Weighted average yield(2)(3) — % — % — % 4.92 % 4.92 % CRT securities:(1) Amortized Cost — — — 14,713 14,713 Estimated fair value — — — 11,417 11,417 Weighted average yield(3) — % — % — % 0.15 % 0.15 % Total available-for-sale debt securities: Amortized cost $ 3,143,171 Estimated fair value $ 3,163,138 December 31, 2019 Residential mortgage-backed securities:(1) Amortized cost $ — $ 1,005 $ — $ 3,986 $ 4,991 Estimated fair value — 1,088 — 4,178 5,266 Weighted average yield(3) — % 5.54 % — % 4.31 % 4.55 % Tax-exempt asset-backed securities:(1) Amortized Cost — — — 183,225 183,225 Estimated fair value — — — 197,027 197,027 Weighted average yield(2)(3) — % — % — % 5.32 % 5.32 % CRT securities:(1) Amortized Cost — — — 14,713 14,713 Estimated fair value — — — 11,964 11,964 Weighted average yield(3) — % — % — % 1.71 % 1.71 % Total available-for-sale debt securities: Amortized cost $ 202,929 Estimated fair value $ 214,257 (1) Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without prepayment penalties. (2) Yields have been adjusted to a tax equivalent basis assuming a 21% federal tax rate. (3) Yields are calculated based on amortized cost. The following table discloses our available-for-sale debt securities that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 or more months: Less Than 12 Months 12 Months or Longer Total (in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss December 31, 2020 U.S. government agency securities $ 98,588 $ (1,412) $ — $ — $ 98,588 $ (1,412) Residential mortgage-backed securities 354,387 (1,128) — — 354,387 (1,128) CRT securities — — 11,417 (3,296) 11,417 (3,296) Total $ 452,975 $ (2,540) $ 11,417 $ (3,296) $ 464,392 $ (5,836) December 31, 2019 CRT securities $ 11,964 $ (2,749) $ — $ — $ 11,964 $ (2,749) Total $ 11,964 $ (2,749) $ — $ — $ 11,964 $ (2,749) Based upon our December 31, 2020 review of securities with unrealized losses we have determined that all losses resulted from factors not deemed credit-related. We have evaluated the near-term prospects of each securities portfolio in relation to the severity of the unrealized losses and adverse conditions related to the securities among other factors. Based on that evaluation management has determined that we have the ability and intent to hold the securities until recovery of fair value and have recorded the unrealized losses in AOCI. Available-for-sale debt securities with carrying values of approximately $31.7 million and $1.9 million were pledged to secure certain customer repurchase agreements and deposits, respectively, at December 31, 2020. The comparative amounts at December 31, 2019 were $3.5 million and $1.2 million, respectively. Equity Securities Equity securities consist of Community Reinvestment Act funds and investments related to our non-qualified deferred compensation plan. At December 31, 2020 and December 31, 2019, we had $33.8 million and $25.6 million, respectively, in equity securities recorded at fair value. The following is a summary of unrealized and realized gains/(losses) recognized on equity securities and included in other non-interest income in the consolidated statements of income: Year Ended December 31, (in thousands) 2020 2019 Net gains/(losses) recognized during the period $ 2,998 $ 2,383 Less: Realized net gains/(losses) recognized during the period on equity securities sold 1,418 119 Unrealized net gains/(losses) recognized during the period on equity securities still held $ 1,580 $ 2,264

Loans Held for Investment and A

Loans Held for Investment and Allowance for Loan Losses	12 Months Ended
	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Loans Held for Investment and Allowance for Loan Losses	Loans Held for Investment and Allowance for Credit Losses on Loans Loans held for investment are summarized by portfolio segment as follows: December 31, (in thousands) 2020 2019 Commercial $ 8,861,580 $ 9,133,444 Energy 766,217 1,425,309 Mortgage finance(1) 9,079,409 8,169,849 Real estate 5,794,624 6,008,040 Gross loans held for investment(2) 24,501,830 24,736,642 Deferred income (net of direct origination costs) (70,970) (90,380) Allowance for credit losses on loans (254,615) (195,047) Total loans held for investment, net(2) $ 24,176,245 $ 24,451,215 (1) Balances at December 31, 2020 and December 31, 2019 are stated net of $1.2 billion and $682.7 million of participations sold, respectively. (2) Excludes accrued interest receivable of $56.5 million and $63.4 million at December 31, 2020 and December 31, 2019, respectively, that is recorded in accrued interest receivable and other assets. The following table summarizes our gross loans held for investment by year of origination and internally assigned credit grades: (in thousands) 2020 2019 2018 2017 2016 2015 and prior Revolving lines of credit Revolving lines of credit converted to term loans Total December 31, 2020 Commercial (1-7) Pass $ 1,259,949 $ 2,816,425 $ 543,438 $ 374,455 $ 192,060 $ 213,212 $ 3,020,353 $ 40,253 $ 8,460,145 (8) Special mention 2,664 115,015 38,751 26,423 1,983 290 19,971 22,797 227,894 (9) Substandard - accruing 15,773 15,854 18,068 32,241 15,297 19,639 22,932 1,641 141,445 (9+) Non-accrual 1,820 8,360 377 1,292 802 15,157 3,836 452 32,096 Total commercial $ 1,280,206 $ 2,955,654 $ 600,634 $ 434,411 $ 210,142 $ 248,298 $ 3,067,092 $ 65,143 $ 8,861,580 Energy (1-7) Pass $ — $ 12,020 $ 7,598 $ 26,931 $ — $ 23,750 $ 553,970 $ — $ 624,269 (8) Special mention — — — — — 13,358 76,866 — 90,224 (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — 5,705 1,972 8,009 36,038 — 51,724 Total energy $ — $ 12,020 $ 7,598 $ 32,636 $ 1,972 $ 45,117 $ 666,874 $ — $ 766,217 Mortgage finance (1-7) Pass $ 755,309 $ 1,063,641 $ 821,122 $ 483,436 $ 106,013 $ 5,849,888 $ — $ — $ 9,079,409 (8) Special mention — — — — — — — — — (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — — — — — — — Total mortgage finance $ 755,309 $ 1,063,641 $ 821,122 $ 483,436 $ 106,013 $ 5,849,888 $ — $ — $ 9,079,409 Real estate CRE (1-7) Pass $ 352,688 $ 892,831 $ 923,762 $ 444,587 $ 208,426 $ 451,283 $ 62,336 $ 61,133 $ 3,397,046 (8) Special mention 3,475 11,170 6,485 88,633 11,153 17,623 — 1,247 139,786 (9) Substandard - accruing — 327 47,708 11,601 32,645 30,766 — 15,940 138,987 (9+) Non-accrual — — — — 5,749 4,852 — — 10,601 RBF (1-7) Pass 162,397 60,077 65,271 3,727 5,888 8,483 551,703 — 857,546 (8) Special mention — 353 — — — — — — 353 (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — — — — — — — Other (1-7) Pass 190,995 150,787 119,696 120,817 82,465 113,105 16,630 39,129 833,624 (8) Special mention — 6,700 2,240 — 1,843 7,195 — 1,018 18,996 (9) Substandard - accruing — — 2,567 14,452 3,301 14,453 — — 34,773 (9+) Non-accrual — — — 927 5,524 6,403 — 14,496 27,350 Secured by 1-4 family (1-7) Pass 58,515 63,031 46,623 54,096 72,527 31,880 4,697 — 331,369 (8) Special mention 646 — — 635 — 1,768 — — 3,049 (9) Substandard - accruing — — — 817 — 109 — — 926 (9+) Non-accrual — — — — — 218 — — 218 Total real estate $ 768,716 $ 1,185,276 $ 1,214,352 $ 740,292 $ 429,521 $ 688,138 $ 635,366 $ 132,963 $ 5,794,624 Total loans held for investment $ 2,804,231 $ 5,216,591 $ 2,643,706 $ 1,690,775 $ 747,648 $ 6,831,441 $ 4,369,332 $ 198,106 $ 24,501,830 The following table details activity in the allowance for credit losses on loans. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. (in thousands) Commercial Energy Mortgage Real Additional Qualitative Reserve Total Year ended December 31, 2020 Beginning balance $ 102,254 $ 60,253 $ 2,265 $ 30,275 $ — $ 195,047 Impact of CECL adoptions (15,740) 24,154 2,031 (1,860) — 8,585 Provision for credit losses on loans 58,630 126,180 403 64,556 — 249,769 Charge-offs 73,360 133,522 — 180 — 207,062 Recoveries 1,277 6,999 — — — 8,276 Net charge-offs (recoveries) 72,083 126,523 — 180 — 198,786 Ending balance $ 73,061 $ 84,064 $ 4,699 $ 92,791 $ — $ 254,615 Year ended December 31, 2019 Beginning balance $ 96,814 $ 34,882 $ — $ 52,595 $ 7,231 $ 191,522 Provision for credit losses on loans 46,738 57,680 2,265 (21,658) (7,231) 77,794 Charge-offs 44,352 32,625 — 662 — 77,639 Recoveries 3,054 316 — — — 3,370 Net charge-offs (recoveries) 41,298 32,309 — 662 — 74,269 Ending balance $ 102,254 $ 60,253 $ 2,265 $ 30,275 $ — $ 195,047 In the first quarter of 2020, we adopted ASU 2016-13, which replaced the incurred loss methodology for determining our provision for credit losses and allowance for credit losses with an expected loss methodology that is referred to as the CECL model. Upon adoption, the allowance for credit losses was increased by $9.1 million, which included a $563,000 increase to the allowance for off-balance sheet credit losses, with no impact to the consolidated statement of income. We recorded a $258.0 million provision for credit losses for the year ended December 31, 2020, compared to $75.0 million for the same period of 2019. We recorded $198.8 million in net charge-offs during the year ended December 31, 2020, compared to $74.3 million during the same period of 2019. Criticized loans total $918.4 million at December 31, 2020 and $584.1 million at December 31, 2019. Criticized loan levels have increased during 2020 as compared to 2019 due to the downgrade of loans to borrowers that have been impacted by the COVID-19 pandemic or that are in categories that are expected to be more significantly impacted by COVID-19. A loan is considered collateral-dependent when the borrower is experiencing financial difficulty and repayment is expected to be provided substantially through the operation or sale of the collateral. The following table summarizes collateral-dependent gross loans held for investment by collateral type as follows: Collateral Type (in thousands) Business Assets Real Property Oil/Gas Mineral Reserves Rolling Stock Total December 31, 2020 Commercial $ 3,361 $ — $ — $ 774 $ 4,135 Energy — — 5,156 — 5,156 Real estate CRE — 4,619 — — 4,619 Other — 11,372 — — 11,372 Total collateral-dependent loans held for investment $ 3,361 $ 15,991 $ 5,156 $ 774 $ 25,282 The table below provides an age analysis of our loans held for investment: (in thousands) 30-59 Days 60-89 Days 90 Days or More Past Due(1) Total Past Non-accrual(2) Current Total Non-accrual With No Allowance December 31, 2020 Commercial $ 6,171 $ 2,602 $ 9,325 $ 18,098 $ 32,096 $ 8,811,386 $ 8,861,580 $ 6,917 Energy — — — — 51,724 714,493 766,217 17,759 Mortgage finance loans — — — — — 9,079,409 9,079,409 — Real estate CRE 2,926 297 — 3,223 10,601 3,672,596 3,686,420 5,749 RBF — — — — — 857,899 857,899 — Other 3,471 493 — 3,964 27,350 883,429 914,743 13,263 Secured by 1-4 family 1,340 1,467 3,216 6,023 218 329,321 335,562 — Total loans held for investment $ 13,908 $ 4,859 $ 12,541 $ 31,308 $ 121,989 $ 24,348,533 $ 24,501,830 $ 43,688 (1) Loans past due 90 days and still accruing includes premium finance loans of $6.4 million. These loans are generally secured by obligations of insurance carriers to refund premiums on canceled insurance policies. The receipt of the refund of premiums from the insurance carriers can take 180 days or longer from the cancellation date. (2) As of December 31, 2020 and December 31, 2019, none of our non-accrual loans were earning interest income on a cash basis. Additionally, no interest income was recognized on non-accrual loans for the year ended December 31, 2020. Accrued interest of $1.3 million was reversed during the year ended December 31, 2020. On January 1, 2020, the date we adopted CECL, non-accrual loans totaled $225.4 million, and included $88.6 million in commercial loans, $125.0 million in energy loans, $9.4 million in CRE loans, $881,000 in real estate-other loans and $1.4 million in secured by 1-4 family loans. As of December 31, 2020 and December 31, 2019, we did not have any loans considered restructured that were not on non-accrual. Of the non-accrual loans at December 31, 2020 and 2019, $45.4 million and $35.1 million, respectively, met the criteria for restructured. These loans had no unfunded commitments at their respective balance sheet dates. The following table details the recorded investment at December 31, 2020 and 2019 of loans that have been restructured during the years ended December 31, 2020 and 2019 by type of modification: Extended Maturity Adjusted Payment Schedule Total (in thousands, except number of contracts) Number of Contracts Balance at Period End Number of Contracts Balance at Period End Number of Contracts Balance at Period End Year Ended December 31, 2020 Commercial 2 $ 7,390 2 $ 14,496 4 $ 21,886 Energy loans 1 5,705 3 12,935 4 18,640 Total 3 $ 13,095 5 $ 27,431 $ 8 $ 40,526 Year Ended December 31, 2019 Commercial 1 $ 1,753 3 $ 21,193 $ 4 $ 22,946 Energy loans 1 3,935 — — 1 3,935 Total 2 $ 5,688 3 $ 21,193 $ 5 $ 26,881 Restructured loans generally include terms to temporarily place the loan on interest only, extend the payment terms or reduce the interest rate. We did not forgive any principal on the above restructured loans. At December 31, 2020 and 2019, all of the above restructured loans were on non-accrual. The restructuring of the loans did not have a significant impact on our allowance for credit losses at December 31, 2020 or 2019. As of December 31, 2020 and 2019, we did not have any loans that were restructured within the last 12 months that subsequently defaulted. In response to the COVID-19 pandemic, we implemented a short-term modification program in late March 2020 to provide temporary payment relief to borrowers who meet the program's qualifications. This program allows for a deferral of payments for 90 days, which we may extend for an additional 90 days, for a maximum of 180 days on a cumulative basis. The deferred payments along with interest accrued during the deferral period are due and payable on the maturity date of the existing loan. Through December 31, 2020, we granted temporary modifications on 483 loans with a total outstanding balance of $1.3 billion, resulting in the deferral of $7.7 million in interest payments. As of December 31, 2020, 48 loans with a total outstanding balance of $90.2 million remain on deferral, of which $50.7 million have been granted a second deferral. Under the applicable guidance, none of these loans were considered restructured as of December 31, 2020.

Certain Transfers of Financial

Certain Transfers of Financial Assets	12 Months Ended
	Dec. 31, 2020
Transfers and Servicing [Abstract]
Certain Transfers of Financial Assets	Certain Transfers of Financial Assets The table below presents a reconciliation of the changes in loans held for sale: Year Ended December 31, (in thousands) 2020 2019 Outstanding balance(1): Beginning balance $ 2,568,362 $ 1,949,785 Loans purchased and originated 11,366,986 10,183,057 Payments and loans sold (13,654,211) (9,564,480) Ending balance 281,137 2,568,362 Fair value adjustment: Beginning balance 8,772 19,689 Increase/(decrease) to fair value (6,744) (10,917) Ending balance 2,028 8,772 Loans held for sale at fair value $ 283,165 $ 2,577,134 (1) Includes $44.1 million and $5.8 million of loans held for sale that are carried at lower of cost or market as of December 31, 2020 and 2019, respectively, as well as $299,000 as of December 31, 2018. At December 31, 2020, we had $7.0 million in in non-accrual loans held for sale, comprised of one loan previously reported in loans held for investment that was transferred to loans held for sale as of December 31, 2020 and subsequently sold at carrying value. At December 31, 2019 there were no non-accrual loans held for sale. At December 31, 2020 and December 31, 2019, we had $16.7 million and $8.2 million, respectively, in loans held for sale that were 90 days or more past due. The $16.7 million in loans held for sale that were 90 days or more past due at December 31, 2020 included $3.3 million of loans guaranteed by U.S. government agencies that were purchased out of Ginnie Mae securities and recorded as loans held for sale, at fair value, on the balance sheet. Interest on these past due loans accrues at the debenture rate guaranteed by the U.S. government. Also included in the $16.7 million were $13.4 million in loans that, pursuant to Ginnie Mae servicing guidelines, we have the unilateral right, but not the obligation, to repurchase if defined delinquent loan criteria are met, and therefore must record as held for sale on our balance sheet regardless of whether the repurchase option has been exercised. At December 31, 2019, $6.0 million of the $8.2 million in loans held for sale that were 90 days or more past due were loans guaranteed by U.S. government agencies that were purchased out of Ginnie Mae securities and recorded as loans held for sale, at fair value, on the balance sheet and $1.9 million were loans that we have the unilateral right, but not the obligation, to repurchase if defined delinquent criteria are met. From time to time we retain the right to service the loans sold through our MCA program, creating MSRs which are recorded as assets on our balance sheet. A summary of MSR activity is as follows: Year Ended December 31, (in thousands) 2020 2019 MSRs: Balance, beginning of year $ 70,707 $ 42,474 Capitalized servicing rights 99,678 39,774 Amortization (38,994) (11,541) Sales — — Balance, end of period $ 131,391 $ 70,707 Valuation allowance: Balance, beginning of year $ 5,803 $ — Increase (decrease) in valuation allowance 20,164 5,803 Balance, end of period $ 25,967 $ 5,803 MSRs, net $ 105,424 $ 64,904 MSRs, fair value $ 105,424 $ 64,904 At December 31, 2020 and 2019, our servicing portfolio of residential mortgage loans had an outstanding principal balance of $13.8 billion and $6.7 billion, respectively. In connection with the servicing of these loans, we hold segregated non-interested-bearing deposit accounts in the name of investors representing escrow funds for taxes and insurance, as well as collections in transit to the investors. These deposits, included in total non-interest-bearing deposits on the consolidated balance sheets, were $152.6 million at December 31, 2020 and $63.7 million at December 31, 2019. At December 31, 2020, the estimated fair value of MSRs was negatively impacted by the increased prepayment speeds from continued low interest rates, which resulted in an impairment charge of $20.2 million being recorded for the year ended December 31, 2020, compared to a $5.8 million impairment charge for the year ended December 31, 2019. To mitigate exposure to potential impairment charges from adverse changes in the fair value of our residential MSR portfolio, we enter into certain derivative contracts as are disclosed in Note 17 - Derivative Financial Instruments. The following summarizes the assumptions used by management to determine the fair value of MSRs: December 31, 2020 2019 Average discount rates 9.09 % 9.06 % Expected prepayment speeds 16.37 % 13.11 % Weighted-average life, in years 4.9 5.8 A sensitivity analysis of changes in the fair value of our MSR portfolio resulting from certain key assumptions is presented in the following table: December 31, (in thousands) 2020 2019 50 bp adverse change in prepayment speed $ (12,203) $ (10,768) 100 bp adverse change in prepayment speed (16,062) (17,965) These sensitivities are hypothetical and actual results may differ materially due to a number of factors. The effect on fair value of a 10% variation in assumptions generally cannot be determined with confidence because the relationship of the change in assumptions to the fair value may not be linear. Additionally, the impact of a variation in a particular assumption on the fair value is calculated while holding other assumptions constant. In reality, changes in one factor may be correlated with changes in other factors, which could impact the sensitivity analysis as presented. In conjunction with the sale and securitization of loans held for sale, we may be exposed to liability resulting from repurchase, indemnification and make-whole agreements. Our estimated exposure related to those agreements totaled $621,000 and $3.6 million at December 31, 2020 and December 31, 2019, respectively, and is recorded in other liabilities in the consolidated

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Leases	Leases Our leases relate primarily to office space and bank branches with remaining lease terms of generally 1 to 13 years. At December 31, 2020, operating lease ROU assets and liabilities were $67.0 million and $82.5 million, respectively, compared to $80.0 million and $95.9 million, respectively, at December 31, 2019. We do not currently have any significant finance leases in which we are the lessee. The table below summarizes our net lease cost: Year Ended December 31, (in thousands) 2020 2019 Operating lease cost $ 15,544 $ 14,844 Short-term lease cost 19 19 Variable lease cost 4,476 3,918 Sublease income (107) (126) Net lease cost $ 19,932 $ 18,655 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 16,568 $ 14,711 Non-cash changes in ROU assets $ 765 $ 98,369 Non-cash changes in lease liabilities(1) $ 784 $ 108,189 (1) Includes $833,000 and $87.9 million in lease liabilities from new ROU assets obtained during the years ended December 31, 2020 and December 31, 2019, respectively. The table below summarizes other information related to our operating leases: December 31, 2020 2019 Weighted-average remaining lease term - operating leases, in years 6.5 7.2 Weighted-average discount rate - operating leases 2.74 % 2.75 % The table below summarizes the maturity of remaining lease liabilities: (in thousands) December 31, 2020 2021 $ 17,222 2022 16,455 2023 16,511 2024 11,754 2025 5,524 2026 and thereafter 22,849 Total lease payments 90,315 Less: Interest (7,786) Present value of lease liabilities $ 82,529

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Goodwill and other intangible assets are summarized as follows: (in thousands) Gross Goodwill and Intangible Assets Accumulated Net Goodwill and Intangible Assets December 31, 2020 Goodwill $ 15,468 $ (374) $ 15,094 Intangible assets—customer relationships and trademarks 9,006 (6,433) 2,573 Total goodwill and intangible assets $ 24,474 $ (6,807) $ 17,667 December 31, 2019 Goodwill $ 15,468 $ (374) $ 15,094 Intangible assets—customer relationships and trademarks 9,006 (6,001) 3,005 Total goodwill and intangible assets $ 24,474 $ (6,375) $ 18,099 Amortization expense related to intangible assets totaled $432,000 in 2020, $471,000 in 2019 and $470,000 in 2018. The estimated aggregate future amortization expense for intangible assets remaining as of December 31, 2020 is as follows: (in thousands) 2021 $ 405 2022 405 2023 382 2024 268 2025 268 Thereafter 845 Total $ 2,573

Premises and Equipment

Premises and Equipment	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Premises and Equipment	Premises and Equipment Premises and equipment are summarized as follows: December 31, (in thousands) 2020 2019 Premises $ 32,231 $ 30,181 Furniture and equipment 41,627 42,176 Total cost 73,858 72,357 Accumulated depreciation (49,312) (41,145) Total premises and equipment, net $ 24,546 $ 31,212 Depreciation expense for the above premises and equipment was approximately $9.5 million, $9.2 million and $9.0 million in 2020, 2019 and 2018, respectively.

Deposits

Deposits	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Deposits	Deposits Deposits are summarized as follows: December 31, (in thousands) 2020 2019 Non-interest-bearing demand deposits $ 12,740,947 $ 9,438,459 Interest-bearing deposits: Transaction 4,396,243 3,651,128 Savings 11,619,880 10,517,975 Time 2,239,519 2,871,031 Total interest-bearing deposits 18,255,642 17,040,134 Total deposits $ 30,996,589 $ 26,478,593 The scheduled maturities of interest-bearing time deposits were as follows at December 31, 2020: (in thousands) 2021 $ 1,317,558 2022 795,656 2023 121,376 2024 1,921 2025 3,003 2026 and after 5 Total $ 2,239,519 At December 31, 2020 and 2019, interest-bearing time deposits of $250,000 or more were approximately $386.9 million and $347.7 million, respectively.

Short-Term and Other Borrowings

Short-Term and Other Borrowings	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Short-Term and Other Borrowings	Borrowings The following table summarizes our short-term and other borrowings: (dollar amounts in thousands) Federal Funds Purchased Customer Repurchase Agreements FHLB Borrowings December 31, 2020 Amount outstanding at year-end $ 107,600 $ 4,151 $ 3,000,000 Interest rate at year-end 0.15 % 0.35 % 0.46 % Average balance outstanding during the year $ 207,121 $ 5,563 $ 2,902,732 Weighted-average interest rate during the year 0.52 % 0.47 % 0.72 % Maximum month-end outstanding during the year $ 300,430 $ 8,314 $ 4,900,000 December 31, 2019 Amount outstanding at year-end $ 132,270 $ 9,496 $ 2,400,000 Interest rate at year-end 1.66 % 0.61 % 1.68 % Average balance outstanding during the year $ 502,604 $ 11,655 $ 2,523,836 Weighted-average interest rate during the year 2.36 % 0.51 % 2.31 % Maximum month-end outstanding during the year $ 905,473 $ 14,208 $ 5,000,000 December 31, 2018 Amount outstanding at year-end $ 629,169 $ 12,005 $ 3,900,000 Interest rate at year-end 2.54 % 0.09 % 2.56 % Average balance outstanding during the year $ 323,140 $ 9,812 $ 1,769,452 Weighted-average interest rate during the year 2.02 % 0.09 % 2.05 % Maximum month-end outstanding during the year $ 629,169 $ 13,835 $ 4,000,000 The following table summarizes our other borrowing capacities net of balances outstanding. As of December 31, 2020, all are scheduled to mature within one year. December 31, (in thousands) 2020 2019 2018 FHLB borrowing capacity relating to loans $ 7,653,317 $ 8,964,019 $ 4,568,842 FHLB borrowing capacity relating to securities 2,946,539 589 721 Total FHLB borrowing capacity(1) $ 10,599,856 $ 8,964,608 $ 4,569,563 Unused federal funds lines available from commercial banks $ 1,030,000 $ 1,432,000 $ 620,000 Unused Federal Reserve borrowings capacity $ 2,179,000 $ 3,637,238 $ 4,933,965 Unused revolving line of credit(2) $ 130,000 $ 130,000 $ 130,000 (1) FHLB borrowings are collateralized by a blanket floating lien on certain real estate secured loans, mortgage finance assets and also certain pledged securities. (2) Unsecured revolving, non-amortizing line of credit with maturity date of December 14, 2021. Proceeds may be used for general corporate purposes, including funding regulatory capital infusions into the Bank. The loan agreement contains customary financial covenants and restrictions. No borrowings were made against this line of credit during 2020, 2019, or 2018.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2020
Subordinated Borrowings [Abstract]
Long-Term Debt	Long-Term Debt From November 2002 to September 2006 various Texas Capital Statutory Trusts were created and subsequently issued floating rate trust preferred securities in various private offerings totaling $113.4 million. As of December 31, 2020, the details of the trust preferred subordinated debentures are summarized below: (dollar amounts in thousands) Texas Capital Texas Capital Texas Capital Texas Capital Texas Capital Date issued November 19, 2002 April 10, 2003 October 6, 2005 April 28, 2006 September 29, 2006 Trust preferred securities issued $10,310 $10,310 $25,774 $25,774 $41,238 Floating or fixed rate securities Floating Floating Floating Floating Floating Interest rate on subordinated debentures 3 month LIBOR + 3.35% 3 month LIBOR + 3.25% 3 month LIBOR + 1.51% 3 month LIBOR + 1.60% 3 month LIBOR + 1.71% Maturity date November 2032 April 2033 December 2035 June 2036 December 2036 On September 21, 2012, the Company issued $111.0 million of subordinated notes. The notes mature in September 2042 and bear interest at a rate of 6.50% per annum, payable quarterly. The indenture governing the notes contains customary covenants and restrictions. On January 31, 2014, the Bank issued $175.0 million of subordinated notes in an offering to institutional investors exempt from registration under Section 3(a)(2) of the Securities Act of 1933 and 12 C.F.R. Part 16. The notes mature in January 2026 and bear interest at a rate of 5.25% per annum, payable semi-annually. The notes are unsecured and are subordinate to the Bank’s obligations to its depositors, its obligations under banker’s acceptances and letters of credit, certain obligations to Federal Reserve Banks and the FDIC and the Bank’s obligations to its other creditors, except any obligations which expressly rank on a parity with or junior to the notes. The notes qualify as Tier 2 capital for regulatory capital purposes, subject to applicable limitations.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense/(benefit) consists of the following: Year ended December 31, (in thousands) 2020 2019 2018 Current: Federal $ 32,701 $ 69,427 $ 82,556 State 920 4,072 3,808 Total 33,621 73,499 86,364 Deferred: Federal (7,964) 10,796 (6,400) State — — — Total (7,964) 10,796 (6,400) Total expense: Federal 24,737 80,223 76,156 State 920 4,072 3,808 Total $ 25,657 $ 84,295 $ 79,964 The reconciliation of income tax at the U.S. federal statutory tax rate to our income tax expense and effective tax rate is as follows: Year ended December 31, 2020 2019 2018 Amount Rate Amount Rate Amount Rate U.S. statutory rate $ 19,309 21 % $ 85,504 21 % $ 79,965 21 % State taxes 726 1 % 3,217 1 % 3,008 1 % Tax-exempt income (3,356) (4) % (5,127) (1) % (4,855) (1) % Tax credits (1,216) (1) % (2,052) (1) % (2,421) (1) % Disallowed FDIC 3,920 4 % 2,468 1 % 2,418 1 % Disallowed compensation 3,098 3 % 628 — % 400 — % Other 3,176 4 % (343) — % 1,449 — % Effective tax rate $ 25,657 28 % $ 84,295 21 % $ 79,964 21 % Our 2020 effective tax rate was significantly impacted by the lower level of income before income taxes experienced in 2020. The tax effect of unrealized gains and losses on available-for-sale debt securities is recorded to other comprehensive income and is not a component of income tax expense/(benefit). At December 31, 2020, 2019 and 2018, we had unrecognized tax benefits of $1.1 million, $1.3 million and $1.6 million, respectively. We are no longer subject to U.S. federal income tax examinations for years before 2017 or state and local income tax examinations for years before 2016. The table below summarizes significant components of our deferred tax assets and liabilities utilizing the federal corporate income tax rate of 21%. Management believes it is more likely than not that all of the deferred tax assets will be realized. In connection with our adoption of CECL, a $2.0 million increase to the deferred tax asset associated with our allowance for credit losses was recorded on January 1, 2020. Our net deferred tax assets are included in other assets in the consolidated balance sheets. December 31, (in thousands) 2020 2019 Deferred tax assets: Allowance for credit losses $ 59,279 $ 44,383 Operating lease liabilities 17,983 20,894 Loan origination fees 11,181 10,638 Stock compensation 3,913 3,605 Non-accrual interest 1,245 2,351 Non-qualified deferred compensation 5,795 4,027 Other 3,136 2,544 Total deferred tax assets 102,532 88,442 Deferred tax liabilities: Loan origination costs (2,997) (2,686) Leases (8,603) (7,912) Operating lease ROU assets (16,617) (19,644) MSRs (22,566) (13,818) Depreciation (14,968) (17,602) Unrealized gain on securities (4,193) (2,379) Other (3,381) (3,337) Total deferred tax liabilities (73,325) (67,378) Net deferred tax asset $ 29,207 $ 21,064

Financial Instruments with Off-

Financial Instruments with Off-Balance Sheet Risk	12 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Financial Instruments with Off-Balance Sheet Risk	Financial Instruments with Off-Balance Sheet Risk The table below presents our financial instruments with off-balance sheet risk, as well as the activity in the allowance for off-balance sheet credit losses related to those financial instruments. This allowance is recorded in other liabilities on the consolidated balance sheet. Year Ended December 31, (in thousands) 2020 2019 Beginning balance of allowance for off-balance sheet credit losses $ 8,640 $ 11,434 Impact of CECL adoption 563 — Provision for off-balance sheet credit losses 8,231 (2,794) Ending balance of allowance for off-balance sheet credit losses $ 17,434 $ 8,640 Commitments to extend credit - period end balance $ 8,530,453 $ 8,066,655 Standby letters of credit - period end balance $ 268,894 $ 261,405

Regulatory Restrictions

Regulatory Restrictions	12 Months Ended
	Dec. 31, 2020
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Regulatory Restrictions	The Company and the Bank are subject to various regulatory capital requirements administered by the federal 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 adverse effect on the Company’s and the Bank’s financial statements. Under capital adequacy guidelines and the regulatory framework for prompt corrective action, the Company and the Bank must meet specific capital guidelines that involve quantitative measures of the Company’s and the Bank’s assets, liabilities, and certain off-balance sheet items as calculated under regulatory accounting practices. The Company’s and the Bank’s capital amounts and classification are also subject to qualitative judgments by the regulators about components, risk weightings and other factors. The Basel III regulatory capital framework (the "Basel III Capital Rules") adopted by U.S. federal regulatory authorities, among other things, (i) establishes the capital measure called "Common Equity Tier 1" ("CET1"), (ii) specifies that Tier 1 capital consist of CET1 and "Additional Tier 1 Capital" instruments meeting stated requirements, (iii) requires that most deductions/adjustments to regulatory capital measures be made to CET1 and not to other components of capital and (iv) defines the scope of the deductions/adjustments to the capital measures. Additionally, the Basel III Capital Rules require that we maintain a 2.5% capital conservation buffer with respect to each of CET1, Tier 1 and total capital to risk-weighted assets, which provides for capital levels that exceed the minimum risk-based capital adequacy requirements. A financial institution with a conservation buffer of less than the required amount is subject to limitations on capital distributions, including dividend payments and stock repurchases, and certain discretionary bonus payments to executive officers. In February 2019, the federal bank regulatory agencies issued a final rule (the "2019 CECL Rule") that revised certain capital regulations to account for changes to credit loss accounting under GAAP. The 2019 CECL Rule included a transition option that allows banking organizations to phase in, over a three-year period, the day-one adverse effects of adopting the new accounting standard related to the measurement of current expected credit losses on their regulatory capital ratios (three-year transition option). In March 2020, the federal bank regulatory agencies issued an interim final rule that maintains the three-year transition option of the 2019 CECL Rule and also provides banking organizations that were required under GAAP to implement CECL before the end of 2020 the option to delay for two years an estimate of the effect of CECL on regulatory capital, relative to the incurred loss methodology's effect on regulatory capital, followed by a three-year transition period (five-year transition option). We adopted CECL on January 1, 2020 and have elected to utilize the five-year transition option. Quantitative measures established by regulation to ensure capital adequacy require the Company and the Bank to maintain minimum amounts and ratios of CET1, Tier 1 and total capital to risk-weighted assets, and of Tier 1 capital to average assets, each as defined in the regulations. Management believes, as of December 31, 2020, that the Company and the Bank meet all capital adequacy requirements to which they are subject. Financial institutions are categorized as well capitalized or adequately capitalized, based on minimum total risk-based, Tier 1 risk-based, CET1 and Tier 1 leverage ratios. As shown in the table below, the Company’s capital ratios exceeded the regulatory definition of adequately capitalized as of December 31, 2020 and 2019. Based upon the information in its most recently filed call report, the Bank met the capital ratios necessary to be well capitalized. The regulatory authorities can apply changes in classification of assets and such changes may retroactively subject the Company to changes in capital ratios. Any such change could reduce one or more capital ratios below well-capitalized status. In addition, a change may result in imposition of additional assessments by the FDIC or could result in regulatory actions that could have a material effect on our condition and results of operations. Because the Bank had less than $15.0 billion in total consolidated assets as of December 31, 2009, we are allowed to continue to classify our trust preferred securities, all of which were issued prior to May 19, 2010, as Tier 1 capital. The table below summarizes our actual and required capital ratios under the Basel III Capital Rules: Actual Minimum capital Required - Basel III Fully Phased-In Required to be Considered Well Capitalized (dollars in thousands) Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio December 31, 2020 CET1 Company $ 2,708,150 9.35 % $ 2,026,400 7.00 % N/A N/A Bank 2,744,211 9.48 % 2,025,417 7.00 % 1,880,745 6.50 % Total capital (to risk-weighted assets) Company 3,498,737 12.09 % 3,039,600 10.50 % N/A N/A Bank 3,375,983 11.67 % 3,038,126 10.50 % 2,893,453 10.00 % Tier 1 capital (to risk-weighted assets) Company 2,968,150 10.25 % 2,460,628 8.50 % N/A N/A Bank 2,904,211 10.04 % 2,459,435 8.50 % 2,314,763 8.00 % Tier 1 capital (to average assets)(1) Company 2,968,150 7.52 % 1,578,651 4.00 % N/A N/A Bank 2,904,211 7.36 % 1,578,207 4.00 % 1,972,758 5.00 % December 31, 2019 CET1 Company $ 2,653,999 8.88 % $ 2,091,591 7.00 % N/A N/A Bank 2,676,513 8.96 % 2,090,870 7.00 % 1,941,522 6.50 % Total capital (to risk-weighted assets) Company 3,398,345 11.37 % 3,137,926 10.50 % N/A N/A Bank 3,262,144 10.92 % 3,136,305 10.50 % 2,986,957 10.00 % Tier 1 capital (to risk-weighted assets) Company 2,912,529 9.75 % 2,540,226 8.50 % N/A N/A Bank 2,835,043 9.49 % 2,538,913 8.50 % 2,389,565 8.00 % Tier 1 capital (to average assets)(1) Company 2,912,529 8.42 % 1,383,640 4.00 % N/A N/A Bank 2,835,043 8.20 % 1,383,190 4.00 % 1,728,988 5.00 % (1) The Tier 1 capital ratio (to average assets) is not impacted by the Basel III Capital Rules; however, the Federal Reserve and the FDIC may require the Company and the Bank, respectively, to maintain a Tier 1 capital ratio (to average assets) above the required minimum. Our mortgage finance loan volumes can increase significantly at month-end, causing a meaningful difference between ending balance and average balance for any period. At December 31, 2020, our mortgage finance loans were $9.1 billion compared to the average for the quarter ended December 31, 2020 of $9.6 billion. As CET1, Tier 1 and total capital ratios are calculated using quarter-end risk-weighted assets and our mortgage finance loans are 100% risk-weighted (excluding MCA mortgage loans held for sale, which receive lower risk weights), the period-end fluctuation in these balances can significantly impact our reported ratios. Due to the actual risk profile and liquidity of this asset class, we manage capital allocated to mortgage finance loans based on changing trends in average balances and do not believe that the period-end balance is representative of risk characteristics that would justify higher allocations. However, we monitor our capital allocation to confirm that all capital levels remain above well-capitalized levels. Dividends that may be paid by banks are routinely restricted by various regulatory authorities. The amount that can be paid in any calendar year without prior approval of our Bank’s regulatory agencies cannot exceed the lesser of the net profits (as defined) for that year plus the net profits for the preceding two calendar years, or retained earnings. The Basel III Capital Rules further limit the amount of dividends that may be paid by our Bank. No dividends were declared or paid on our common stock during 2020, 2019 or 2018. On March 15, 2020, to encourage banks to lend all available funds during the COVID-19 pandemic, the Federal Reserve announced it had reduced the reserve requirement ratio to zero effective March 26, 2020 and continuing through December 31, 2020. The required reserve balances at the Federal Reserve at December 31, 2019 was approximately $283.4 million.

Stock-Based Compensation and Em

Stock-Based Compensation and Employee Benefits	12 Months Ended
	Dec. 31, 2020
Compensation Related Costs [Abstract]
Stock-Based Compensation and Employee Benefits	Stock-Based Compensation and Employee Benefits We have a qualified retirement plan with a salary deferral feature designed to qualify under Section 401 of the Internal Revenue Code (“the 401(k) Plan”). The 401(k) Plan permits our employees to defer a portion of their compensation. Matching contributions may be made in amounts and at times determined by the Company. We contributed approximately $10.3 million, $9.5 million, and $9.6 million for the years ended December 31, 2020, 2019 and 2018, respectively. Employees are eligible to participate in the 401(k) Plan when they meet certain requirements concerning minimum age and period of credited service. All contributions to the 401(k) Plan are invested in accordance with participant elections among certain investment options. We also offer a non-qualified deferred compensation plan for our executives and key members of management in order to assist us in attracting and retaining these individuals. Participants in the plan may elect to defer up to 75% of their annual salary and/or short-term incentive payout into deferral accounts that mirror the gains or losses of investments selected by the participants. The plan allows us to make discretionary contributions on behalf of a participant as well as matching contributions. We made matching contributions of $1.0 million in each of 2020, 2019 and 2018. All participant contributions to the plan and any related earnings are immediately vested and may be withdrawn upon the participant's separation from service, death or disability or upon a date specified by the participant. Salary deferrals are recorded as salaries and employee benefits expense in the consolidated statements of income with an offsetting payable to participants in other liabilities on the consolidated balance sheets. We have an Employee Stock Purchase Plan (“ESPP”). Employees are eligible for the ESPP when they meet certain requirements concerning period of credited service and minimum hours worked. Eligible employees may contribute a between 1% and 10% of eligible compensation up to the Section 423 of the Internal Revenue Code limit of $25,000. Employee contributions to the ESPP were temporarily suspended throughout 2020. On January 1, 2021, the suspension was removed and employee contributions commenced. In 2006, stockholders approved the ESPP, which allocated 400,000 shares for purchase. As of December 31, 2020, 2019 and 2018, 155,933, 155,933 and 143,348 shares had been purchased on behalf of employees under the ESPP. We have stock-based compensation plans under which equity-based compensation grants are made by the board of directors, or its designated committee. Grants are subject to vesting requirements. Under the plans, we may grant, among other things, non-qualified stock options, incentive stock options, restricted stock, restricted stock units (“RSUs”), stock appreciation rights (“SARs”), cash-settled performance units or any combination thereof to employees and non-employee directors. A total of 2,550,000 shares are authorized for grant under the plans. Total shares remaining available for grant under the plans at December 31, 2020 were 1,203,294. A summary of our SAR activity and related information is as follows. Grants of SARs include time-based vesting conditions that generally vest ratably over a period of five years. December 31, 2020 December 31, 2019 December 31, 2018 SARs Weighted Average Exercise Price SARs Weighted Average Exercise Price SARs Weighted Average Exercise Price SARs outstanding at beginning of year 21,200 $ 33.95 41,350 $ 29.13 74,363 $ 30.12 SARs exercised (8,800) 20.52 (20,150) 24.07 (33,013) 31.35 SARs outstanding at year-end 12,400 $ 43.48 21,200 $ 33.95 41,350 $ 29.13 SARs vested and exercisable at year-end 12,400 $ 43.48 21,200 $ 33.95 39,750 $ 27.81 Weighted average remaining contractual life of SARs vested (in years) 2.26 2.14 2.33 Weighted average remaining contractual life of SARs outstanding (in years) 2.26 2.14 2.44 Compensation expense $ — $ 6,000 $ 121,000 Unrecognized compensation expense $ — $ — $ 6,000 Weighted average period over which unrecognized compensation expense is expected to be recognized (in years) 0.00 0.00 0.17 Fair value of shares vested during the year $ — $ 37,000 $ 211,000 Intrinsic value of SARs exercised $ 294,000 $ 724,000 $ 1,919,000 A summary of our RSU activity and related information is as follows. Grants of RSUs include time-based vesting conditions that generally vest ratably over a period of three three four December 31, 2020 December 31, 2019 December 31, 2018 RSUs Weighted RSUs Weighted RSUs Weighted RSUs outstanding at beginning of year 558,312 $ 64.95 349,533 $ 69.11 423,732 $ 60.01 RSUs granted 631,092 39.37 386,913 59.28 95,891 88.07 RSUs vested (171,494) 65.17 (140,666) 59.97 (121,507) 54.97 RSUs forfeited (62,316) 56.92 (37,468) 62.73 (48,583) 63.60 RSUs outstanding at year-end 955,594 $ 48.76 558,312 $ 64.95 349,533 $ 69.11 Compensation expense $ 15,655,000 $ 11,733,000 $ 8,803,000 Unrecognized compensation expense $ 29,146,000 $ 25,305,000 $ 16,538,000 Weighted average period over which unrecognized compensation expense is expected to be recognized (in years) 2.83 3.09 2.90 New non-employee directors receive grants of restricted common stock as to which restrictions lapse ratably over a period of three years. Compensation expense for these grants was $26,000, $36,000 and $62,000 for the years ended December 31, 2020, 2019 and 2018, respectively. Total compensation cost for all share-based arrangements was $15.7 million, $11.8 million and $9.0 million for the years ended December 31, 2020, 2019 and 2018, respectively. Cash-settled units totaling 59,285 were outstanding at December 31, 2020, all of which are time-based and vest ratably over a period of four years. We granted 138,773 cash-settled units in 2018. No grants were made in 2020 or 2019. Since these units have a cash payout feature, they are accounted for under the liability method with related expense based on the stock price at period end. Compensation cost for the cash-settled units was $1.8 million, $5.8 million and $8.0 million for the years ended December 31, 2020, 2019 and 2018, respectively.

Fair Value Disclosures

Fair Value Disclosures	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Disclosures	Fair Value DisclosuresWe determine the fair market values of our assets and liabilities measured at fair value on a recurring and nonrecurring basis using the fair value hierarchy as prescribed in ASC 820. See Note 1 - Operations and Summary of Significant Accounting Policies for information regarding the fair value hierarchy and a description of the methods and significant assumptions used by the Company is estimating its fair value disclosures for financial statements. Assets and liabilities measured at fair value are as follows: Fair Value Measurements Using (in thousands) Level 1 Level 2 Level 3 December 31, 2020 Available-for-sale debt securities:(1) U.S. government agency securities $ — $ 123,589 $ — Residential mortgage-backed securities — 2,828,956 — Tax-exempt asset-backed securities — — 199,176 CRT Securities — — 11,417 Equity securities(1)(2) 26,593 7,239 — Loans held for sale(3) — 232,147 6,933 Loans held for investment(4) — — 21,209 Derivative assets(5) — 102,720 — Derivative liabilities(5) — 99,255 — Non-qualified deferred compensation plan liabilities(6) 26,593 — — December 31, 2019 Available-for-sale debt securities:(1) Residential mortgage-backed securities $ — $ 5,266 $ — Tax-exempt asset-backed securities — — 197,027 CRT Securities — — 11,964 Equity securities(1)(2) 18,484 7,130 — Loans held for sale(3) — 2,564,281 7,043 Loans held for investment(4) — — 109,585 Derivative assets(5) — 48,684 — Derivative liabilities(5) — 51,310 — Non-qualified deferred compensation plan liabilities(6) 18,484 — — (1) Securities are measured at fair value on a recurring basis, generally monthly, except for tax-exempt asset-backed securities and CRT securities which are measured quarterly. (2) Equity securities consist of Community Reinvestment Act funds and investments related to our non-qualified deferred compensation plan. (3) Loans held for sale purchased through our MCA program are measured at fair value on a recurring basis, generally monthly. (4) Includes certain collateral-dependent loans held for investment for which a specific allocation of the allowance for credit losses is based upon the fair value of the loan’s underlying collateral. These loans held for investment are measured on a nonrecurring basis, generally annually or more often as warranted by market and economic conditions. (5) Derivative assets and liabilities are measured at fair value on a recurring basis, generally quarterly. (6) Non-qualified deferred compensation plan liabilities represent the fair value of the obligation to the employee, which generally corresponds to the fair value of the invested assets, and are measured at fair value on a recurring basis, generally monthly. Level 3 Valuations The following table presents a reconciliation of the level 3 fair value category measured at fair value on a recurring basis: Net Realized/Unrealized Gains (Losses) (in thousands) Balance at Beginning of Period Purchases / Additions Sales / Reductions Realized Unrealized Balance at End of Period Year ended December 31, 2020 Available-for-sale debt securities:(1) Tax-exempt asset-backed securities $ 197,027 $ 8,470 $ (6,755) $ — $ 434 $ 199,176 CRT Securities $ 11,964 $ — $ — $ — $ (547) $ 11,417 Loans held for sale(2) $ 7,043 $ 1,472 $ (2,077) $ 248 $ 247 $ 6,933 Year ended December 31, 2019 Available-for-sale debt securities:(1) Tax-exempt asset-backed securities $ 95,804 $ 92,010 $ (4,302) $ — $ 13,515 $ 197,027 CRT Securities $ — $ 15,044 $ — $ (331) $ (2,749) $ 11,964 Loans held for sale(2) $ 16,415 $ 321 $ (10,690) $ 190 $ 807 $ 7,043 (1) Unrealized gains/(losses) on available-for-sale debt securities are recorded in AOCI and relate to assets that remain outstanding at period end. Realized gains/(losses) are recorded in other non-interest income. (2) Realized and unrealized gains/(losses) on loans held for sale are recorded in gain/(loss) on sale of loans held for sale. Tax-exempt asset-backed securities The fair value of tax-exempt asset-backed securities is based on a discounted cash flow model, which utilizes Level 3, or unobservable, inputs, the most significant of which were a discount rate and weighted-average life. At December 31, 2020, the discount rates utilized ranged from 2.44% to 2.53% and the weighted-average life ranged from 5.51 years to 5.54 years. On a combined amortized cost weighted-average basis a discount rate of 2.49% and a weighted-average life of 5.53 years were utilized to determine the fair value of these securities at December 31, 2020. At December 31, 2019, the combined weighted-average discount rate and weighted-average life utilized were 2.99% and 7.00 years, respectively. CRT securities The fair value of CRT securities is based on a discounted cash flow model, which utilizes Level 3, or unobservable, inputs, the most significant of which were a discount rate and weighted-average life. At December 31, 2020, the discount rates utilized ranged from 2.75% to 7.59% and the weighted-average life ranged from 5.97 years to 10.54 years. On a combined amortized cost weighted-average basis a discount rate of 4.36% and a weighted-average life of 7.49 years were utilized to determine the fair value of these securities at December 31, 2020. At December 31, 2019, the combined weighted-average discount rate and weighted-average life utilized were 4.54% and 9.33 years, respectively. Loans held for sale The fair value of loans held for sale using Level 3 inputs include loans that cannot be sold through normal sale channels and thus require significant management judgment or estimation when determining the fair value. The fair value of such loans is generally based upon quoted prices of comparable loans with a liquidity discount applied. At December 31, 2020, the fair value of these loans was calculated using a weighted-average discounted price of 97.2%, compared to 94.1% at December 31, 2019. Loans held for investment Certain collateral-dependent loans held for investment are reported at fair value when, based upon an individual evaluation, the specific allocation of the allowance for credit losses that is deducted from the loan's amortized cost is based upon the fair value of the loan's underlying collateral. The $21.2 million fair value of loans held for investment at December 31, 2020 reported above includes loans held for investment with a carrying value of $25.3 million that were reduced by specific allowance allocations totaling $4.1 million based on collateral valuations utilizing Level 3 inputs. The $109.6 million fair value of loans held for investment at December 31, 2019 reported above includes impaired loans with a carrying value of $145.4 million that were reduced by specific allowance allocations totaling $35.8 million based on collateral valuations utilizing Level 3 inputs. Fair Value of Financial Instruments A summary of the carrying amounts and estimated fair values of financial instruments is as follows: December 31, 2020 December 31, 2019 (in thousands) Carrying Estimated Carrying Estimated Financial assets: Level 1 inputs: Cash and cash equivalents $ 9,206,380 $ 9,206,380 $ 4,425,583 $ 4,425,583 Investment securities 26,593 26,593 18,484 18,484 Level 2 inputs: Investment securities 2,959,784 2,959,784 12,396 12,396 Loans held for sale 232,147 232,147 2,570,091 2,570,091 Derivative assets 102,720 102,720 48,684 48,684 Level 3 inputs: Investment securities 210,593 210,593 208,991 208,991 Loans held for sale 6,933 6,933 7,043 7,043 Loans held for investment, net 24,176,245 24,233,185 24,451,215 24,478,586 Financial liabilities: Level 2 inputs: Federal funds purchased 107,600 107,600 132,270 132,270 Customer repurchase agreements 4,151 4,151 9,496 9,496 Other borrowings 3,000,000 3,000,000 2,400,000 2,400,000 Subordinated notes 282,490 291,704 282,129 292,302 Trust preferred subordinated debentures 113,406 113,406 113,406 113,406 Derivative liabilities 99,255 99,255 51,310 51,310 Level 3 inputs: Deposits 30,996,589 30,997,980 26,478,593 26,486,090

Parent Company Only

Parent Company Only	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Parent Company Only	Parent Company Only Summarized financial information for Texas Capital Bancshares, Inc. are as follows: Balance Sheet December 31, (in thousands) 2020 2019 Assets Cash and cash equivalents $ 57,472 $ 71,462 Loans held for investment (net of unearned income) 7,500 10,500 Investment in subsidiaries 2,930,843 2,847,393 Other assets 89,551 88,639 Total assets $ 3,085,366 $ 3,017,994 Liabilities and Stockholders’ Equity Other liabilities $ 1,320 $ 1,768 Subordinated notes 108,816 108,715 Trust preferred subordinated debentures 113,406 113,406 Total liabilities 223,542 223,889 Preferred stock 150,000 150,000 Common stock 504 503 Additional paid-in capital 1,002,050 988,357 Retained earnings 1,693,504 1,646,303 Treasury stock (8) (8) Accumulated other comprehensive income 15,774 8,950 Total stockholders’ equity 2,861,824 2,794,105 Total liabilities and stockholders’ equity $ 3,085,366 $ 3,017,994 Statement of Income Year ended December 31, (in thousands) 2020 2019 2018 Interest on loans $ 3,402 $ 3,401 $ 3,398 Dividend income 10,400 10,400 10,400 Other income 96 151 142 Total income 13,898 13,952 13,940 Other non-interest income 3 17 7 Interest expense 10,515 12,342 12,031 Salaries and employee benefits 725 607 588 Legal and professional 3,238 3,093 2,020 Other non-interest expense 4,553 1,889 2,013 Total expense 19,031 17,931 16,652 Income (loss) before income taxes and equity in undistributed income of subsidiary (5,130) (3,962) (2,705) Income tax expense (benefit) (1,135) (861) (587) Income (loss) before equity in undistributed income of subsidiary (3,995) (3,101) (2,118) Equity in undistributed income of subsidiary 68,100 312,932 293,321 Net income 64,105 309,831 291,203 Preferred stock dividends 9,750 9,750 9,750 Net income available to common stockholders $ 54,355 $ 300,081 $ 281,453 Statements of Cash Flows Year ended December 31, (in thousands) 2020 2019 2018 Operating Activities Net income $ 64,105 $ 309,831 $ 291,203 Adjustments to reconcile net income to net cash used in operating activities: Equity in undistributed income of subsidiary (68,100) (312,932) (293,321) Amortization 101 101 101 Increase in other assets (912) (1,187) (1,152) Increase (decrease) in other liabilities (448) 297 227 Net cash used in operating activities (5,254) (3,890) (2,942) Investing Activities Net (increase)/decrease in loans held for investment 3,000 (3,000) — Investments in and advances to subsidiaries — — (40,000) Net cash provided by/(used in) investing activities 3,000 (3,000) (40,000) Financing Activities Proceeds from sale of stock related to stock-based awards (1,986) (1,459) (2,382) Preferred dividends paid (9,750) (9,750) (9,750) Net cash used in financing activities (11,736) (11,209) (12,132) Net decrease in cash and cash equivalents (13,990) (18,099) (55,074) Cash and cash equivalents at beginning of year 71,462 89,561 144,635 Cash and cash equivalents at end of year $ 57,472 $ 71,462 $ 89,561

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Financial Instruments	Derivative Financial Instruments The notional amounts and estimated fair values of derivative positions outstanding are presented in the following table: December 31, 2020 December 31, 2019 Estimated Fair Value Estimated Fair Value (in thousands) Notional Asset Derivative Liability Derivative Notional Asset Derivative Liability Derivative Non-hedging derivatives: Financial institution counterparties: Commercial loan/lease interest rate swaps $ 1,922,956 $ 71 $ 96,246 $ 1,548,234 $ 182 $ 46,518 Commercial loan/lease interest rate caps 565,634 34 — 639,163 32 — Foreign currency forward contracts 6,667 214 78 2,219 169 — Customer counterparties: Commercial loan/lease interest rate swaps 1,922,956 96,246 71 1,548,234 46,518 182 Commercial loan/lease interest rate caps 565,634 — 34 639,163 — 32 Foreign currency forward contracts 6,667 78 214 2,219 — 169 Economic hedging derivatives to hedge: Residential MSRs: Interest rate swap futures 320,000 474 — — — — Forward sale commitments 155,000 551 — — — — Loans held for sale: Loan purchase commitments 332,145 5,123 8 214,012 1,965 4 Forward sale commitments 485,326 — 2,675 2,654,653 — 4,587 Gross derivatives 102,791 99,326 48,866 51,492 Offsetting derivative assets/liabilities (71) (71) (182) (182) Net derivatives included in the consolidated balance sheets $ 102,720 $ 99,255 $ 48,684 $ 51,310 The weighted-average received and paid interest rates for interest rate swaps outstanding were as follows: December 31, 2020 December 31, 2019 Received Paid Received Paid Non-hedging interest rate swaps 3.14 % 1.38 % 3.94 % 3.26 % The weighted-average strike rate for outstanding interest rate caps was 3.41% at December 31, 2020 and 3.29% at December 31, 2019. Our credit exposure on derivative instruments is limited to the net favorable value and interest payments by each counterparty. In some cases collateral may be required from the counterparties involved if the net value of the derivative instruments exceeds a nominal amount. Our credit exposure associated with these instruments, net of any collateral pledged, was approximately $102.7 million at December 31, 2020 and approximately $48.7 million at December 31, 2019. Collateral levels are monitored and adjusted on a regular basis for changes in interest rate swap and cap values, as well as for changes in the value of forward sale commitments. At December 31, 2020, we had $108.3 million in cash collateral pledged for these derivatives, of which $104.4 million was included in interest-bearing deposits in other banks and $3.9 million was included in accrued interest receivable and other assets. At December 31, 2019, we had $56.6 million in cash collateral pledged for these derivatives, of which $54.3 million was included in interest-bearing deposits and $2.3 million was included in accrued interest receivable and other assets. We also enter into credit risk participation agreements with financial institution counterparties for interest rate swaps related to loans in which we are either a participant or a lead bank. The risk participation agreements entered into by us as a participant bank provide credit protection to the financial institution counterparty should the borrower fail to perform on its interest rate derivative contract with that financial institution. We are party to 9 risk participation agreements where we are a participant bank with a notional amount of $119.5 million at December 31, 2020, compared to 12 risk participation agreements having a notional amount of $146.7 million at December 31, 2019. The maximum estimated exposure to these agreements, assuming 100% default by all obligors, was approximately $6.0 million at December 31, 2020 and $3.6 million at December 31, 2019. The fair value of these exposures was insignificant to the consolidated financial statements at both December 31, 2020 and December 31, 2019. Risk participation agreements entered into by us as the lead bank provide credit protection to us should the borrower fail to perform on its interest rate derivative contract with us. We are party to 16 risk participation agreements where we are the lead bank having a notional amount of $165.9 million at December 31, 2020, compared to 12 agreements having a notional amount of $145.9 million at December 31, 2019.

Quarterly Financial Data

Quarterly Financial Data	12 Months Ended
	Dec. 31, 2020
Selected Quarterly Financial Information [Abstract]
Quarterly Financial Information	Quarterly Financial Data (unaudited) The tables below summarize our quarterly financial information: 2020 Selected Quarterly Financial Data (in thousands, except per share data) Fourth Third Second First Interest income $ 255,163 $ 243,731 $ 252,010 $ 306,008 Interest expense 32,153 36,162 42,082 77,689 Net interest income 223,010 207,569 209,928 228,319 Provision for credit losses 32,000 30,000 100,000 96,000 Net interest income after provision for credit losses 191,010 177,569 109,928 132,319 Non-interest income 42,886 60,348 70,502 11,780 Non-interest expense 150,886 165,741 222,352 165,417 Income/(loss) before income taxes 83,010 72,176 (41,922) (21,318) Income tax expense/(benefit) 22,834 15,060 (7,606) (4,631) Net income/(loss) 60,176 57,116 (34,316) (16,687) Preferred stock dividends 2,437 2,438 2,437 2,438 Net income/(loss) available to common stockholders $ 57,739 $ 54,678 $ (36,753) $ (19,125) Basic earnings/(loss) per share: $ 1.14 $ 1.08 $ (0.73) $ (0.38) Diluted earnings/(loss) per share: $ 1.14 $ 1.08 $ (0.73) $ (0.38) 2019 Selected Quarterly Financial Data (in thousands, except per share data) Fourth Third Second First Interest income $ 337,757 $ 355,101 $ 346,893 $ 325,561 Interest expense 89,372 102,933 103,340 89,947 Net interest income 248,385 252,168 243,553 235,614 Provision for credit losses 17,000 11,000 27,000 20,000 Net interest income after provision for credit losses 231,385 241,168 216,553 215,614 Non-interest income 17,761 20,301 24,364 30,014 Non-interest expense 168,187 149,429 141,718 141,516 Income before income taxes 80,959 112,040 99,199 104,112 Income tax expense 16,539 23,958 21,387 22,411 Net income 64,420 88,082 77,812 81,701 Preferred stock dividends 2,437 2,438 2,437 2,438 Net income available to common stockholders $ 61,983 $ 85,644 $ 75,375 $ 79,263 Basic earnings per share: $ 1.23 $ 1.70 $ 1.50 $ 1.58 Diluted earnings per share: $ 1.23 $ 1.70 $ 1.50 $ 1.58

New Accounting Standards

New Accounting Standards	12 Months Ended
	Dec. 31, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
New Accounting Standards	New Accounting Standards ASU 2019-12 "Income Taxes (Topic 740)" ("ASU 2019-12") simplifies the accounting for income taxes by removing certain exceptions and improves the consistent application of GAAP by clarifying and amending other existing guidance. ASU 2019-012 will be effective for us on January 1, 2021 and is not expected to have any material impact on our consolidated financial statements. ASU 2020-01 "Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)" ("ASU 2020-01") clarifies the interaction of the accounting for equity securities under Topic 321 and investments accounted for under the equity method of accounting in Topic 323 and the accounting for certain forward contracts and purchased options accounted for under Topic 815. ASU 2020-01 will be effective for us on January 1, 2021 and is not expected to have any material impact on our consolidated financial statements. ASU 2020-02 "Financial Instruments - Credit Losses (Topic 326) and Leases (Topic 842)" ("ASU 2020-02") incorporates SEC SAB 119 (updated from SAB 102) into the Accounting Standards Codification (the "Codification") by aligning SEC recommended policies and procedures with ASC 326. ASU 2020-02 was effective on January 1, 2020 and has not had a significant impact on our documentation requirements. ASU 2020-03 "Codification Improvements to Financial Instruments" ("ASU 2020-03") revised a wide variety of topics in the Codification with the intent to make the Codification easier to understand and apply by eliminating inconsistencies and providing clarifications. ASU 2020-03 was effective immediately upon its release in March 2020 and did not have a material impact on our consolidated financial statements. ASU 2020-04, "Reference Rate Reform (Topic 848)" ("ASU 2020-04") provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. For transactions that are modified because of reference rate reform and that meet certain scope guidance (i) modifications of loan agreements should be accounted for by prospectively adjusting the effective interest rate and the modification will be considered "minor" so that any existing unamortized origination fees/costs would carry forward and continue to be amortized and (ii) modifications of lease agreements should be accounted for as a continuation of the existing agreement with no reassessments of the lease classification and the discount rate or remeasurements of lease payments that otherwise would be required for modifications not accounted for as separate contracts. ASU 2020-04 also provides numerous optional expedients for derivative accounting. ASU 2020-04 is effective March 12, 2020 through December 31, 2022. An entity may elect to apply ASU 2020-04 for contract modifications as of January 1, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. Once elected for a Topic or an Industry Subtopic within the Codification, the amendments in this ASU must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. We anticipate this ASU will simplify any modifications we execute between the selected start date (yet to be determined) and December 31, 2022 that are directly related to LIBOR transition by allowing prospective recognition of the continuation of the contract, rather than extinguishment of the old contract resulting in writing off unamortized fees/costs. We are evaluating the impacts of this ASU and have not yet determined whether this ASU will have material effects on our business operations and consolidated financial statements.

Operations and Summary of Sig_2

Operations and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Nature of Business	Organization and Nature of Business Texas Capital Bancshares, Inc. (the "Company” or "TCBI"), 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 Texas Capital Bancshares, Inc. and its wholly owned subsidiary, Texas Capital Bank, National Association (the "Bank”). We serve the needs of commercial businesses and successful 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 or with operations in Texas. Our national lines of business provide specialized leading products to businesses throughout the United States. On December 9, 2019, the Company and IBTX entered into the Merger Agreement, pursuant to which, on the terms and subject to the conditions therein, the Company would be merged with and into IBTX. On May 22, 2020, the Company and IBTX entered into an agreement pursuant to which the parties mutually agreed to terminate the Merger Agreement. Neither party paid a termination fee in connection with the termination of the Merger Agreement.
Basis of Presentation	Basis of PresentationOur 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.
Accounting Changes	Accounting Changes On January 1, 2020, we adopted ASU 2016-13 "Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments" ("ASU 2016-13"), which replaces the incurred loss methodology for determining our provision for credit losses and allowance for credit losses with an expected loss methodology that is referred to as the Current Expected Credit Loss ("CECL") model. The measurement of expected credit losses under the CECL methodology is applicable to financial assets measured at amortized cost, including loan receivables and held-to-maturity debt securities. It also applies to off-balance sheet credit exposures not accounted for as insurance (loan commitments, standby letters of credit, financial guarantees, and other similar instruments) and net investments in leases recognized by a lessor in accordance with ASU 2016-02 "Leases (Topic 842)" . In addition, ASU 2016-13 made changes to the accounting for available-for-sale debt securities. One such change is to require credit-related impairments to be recognized in the allowance for credit losses rather than as a write-down of the securities' amortized cost basis when management does not intend to sell or believes that it is not more likely than not that they will be required to sell the securities prior to recovery of the securities amortized cost basis. We adopted ASU 2016-13 using the modified retrospective method for all financial assets measured at amortized cost, off-balance sheet credit exposures and net investments in leases. Results for reporting periods beginning after January 1, 2020 are presented under ASU 2016-13 while prior period amounts continue to be reported in accordance with previously applicable GAAP. Our accounting policies changed significantly upon the adoption of CECL on January 1, 2020. Prior to January 1, 2020, the allowance for loan losses was based on incurred credit losses in accordance with accounting policies disclosed in Note 1 - Operations and Summary of Significant Accounting Policies in the accompanying notes to the consolidated financial statements included in our Annual Report on Form 10-K for the year-ended December 31, 2019. We adopted ASU 2016-13 using the prospective transition approach for debt securities for which other-than-temporary impairment had been recognized prior to January 1, 2020. As a result, the amortized cost basis remains the same before and after the effective date of ASU 2016-13. The following table illustrates the impact of adopting ASU 2016-13 and details how outstanding loan balances have been reclassified as a result of changes made to our primary portfolio segments under CECL: January 1, 2020 (in thousands) As Reported Under ASU 2016-13 Pre-ASU 2016-13 Impact of ASU 2016-13 Adoption Assets: Loans held for investment (outstanding balance) Commercial $ 9,133,444 $ 10,230,828 $ (1,097,384) Energy 1,425,309 1,425,309 Mortgage finance 8,169,849 8,169,849 — Construction 2,563,339 (2,563,339) Real estate 6,008,040 3,444,701 2,563,339 Consumer 71,463 (71,463) Equipment leases 256,462 (256,462) Allowance for credit losses on loans (203,632) (195,047) (8,585) Total loans held for investment, net 24,442,630 24,451,215 (8,585) Net deferred tax asset 23,058 21,064 1,994 Liabilities: Allowance for credit losses on off-balance sheet exposures 9,203 8,640 563 Equity: Retained earnings 1,656,517 1,663,671 (7,154) In connection with our adoption of ASU 2016-13, changes were made to our primary portfolio segments to align with the methodology applied in determining the allowance under CECL. These changes included segregating energy loans into a stand-alone portfolio segment and reclassifying consumer and equipment leases into the commercial loan portfolio segment. Additionally, construction and real estate loans were combined into a single portfolio segment, referred to as real estate. The real estate loan portfolio segment includes loans further categorized as commercial real estate, residential homebuilder finance, secured by 1-4 family and an "other" category. See Allowance for Credit Losses below for further discussion of these portfolio segments. ASU 2019-12 "Income Taxes (Topic 740)" ("ASU 2019-12") simplifies the accounting for income taxes by removing certain exceptions and improves the consistent application of GAAP by clarifying and amending other existing guidance. ASU 2019-012 will be effective for us on January 1, 2021 and is not expected to have any material impact on our consolidated financial statements. ASU 2020-01 "Investments - Equity Securities (Topic 321), Investments - Equity Method and Joint Ventures (Topic 323), and Derivatives and Hedging (Topic 815)" ("ASU 2020-01") clarifies the interaction of the accounting for equity securities under Topic 321 and investments accounted for under the equity method of accounting in Topic 323 and the accounting for certain forward contracts and purchased options accounted for under Topic 815. ASU 2020-01 will be effective for us on January 1, 2021 and is not expected to have any material impact on our consolidated financial statements. ASU 2020-02 "Financial Instruments - Credit Losses (Topic 326) and Leases (Topic 842)" ("ASU 2020-02") incorporates SEC SAB 119 (updated from SAB 102) into the Accounting Standards Codification (the "Codification") by aligning SEC recommended policies and procedures with ASC 326. ASU 2020-02 was effective on January 1, 2020 and has not had a significant impact on our documentation requirements. ASU 2020-03 "Codification Improvements to Financial Instruments" ("ASU 2020-03") revised a wide variety of topics in the Codification with the intent to make the Codification easier to understand and apply by eliminating inconsistencies and providing clarifications. ASU 2020-03 was effective immediately upon its release in March 2020 and did not have a material impact on our consolidated financial statements. ASU 2020-04, "Reference Rate Reform (Topic 848)" ("ASU 2020-04") provides optional expedients and exceptions for applying GAAP to loan and lease agreements, derivative contracts, and other transactions affected by the anticipated transition away from LIBOR toward new interest rate benchmarks. For transactions that are modified because of reference rate reform and that meet certain scope guidance (i) modifications of loan agreements should be accounted for by prospectively adjusting the effective interest rate and the modification will be considered "minor" so that any existing unamortized origination fees/costs would carry forward and continue to be amortized and (ii) modifications of lease agreements should be accounted for as a continuation of the existing agreement with no reassessments of the lease classification and the discount rate or remeasurements of lease payments that otherwise would be required for modifications not accounted for as separate contracts. ASU 2020-04 also provides numerous optional expedients for derivative accounting. ASU 2020-04 is effective March 12, 2020 through December 31, 2022. An entity may elect to apply ASU 2020-04 for contract modifications as of January 1, 2020, or prospectively from a date within an interim period that includes or is subsequent to March 12, 2020, up to the date that the financial statements are available to be issued. Once elected for a Topic or an Industry Subtopic within the Codification, the amendments in this ASU must be applied prospectively for all eligible contract modifications for that Topic or Industry Subtopic. We anticipate this ASU will simplify any modifications we execute between the selected start date (yet to be determined) and December 31, 2022 that are directly related to LIBOR transition by allowing prospective recognition of the continuation of the contract, rather than extinguishment of the old contract resulting in writing off unamortized fees/costs. We are evaluating the impacts of this ASU and have not yet determined whether this ASU will have material effects on our business operations and consolidated financial statements.
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.
Basic and Diluted Earnings Per Common Share	Basic and Diluted Earnings Per Common Share Basic earnings per common share is based on net income available to common stockholders divided by the weighted-average number of common shares outstanding during the period excluding non-vested stock. Diluted earnings per common share include the dilutive effect of non-vested stock-based awards granted using the treasury stock method. A reconciliation of the weighted-average shares used in calculating basic earnings per common share and the weighted average common shares used in calculating diluted earnings per common share for the reported periods is provided in Note 2 — Earnings Per Share.
Accumulated Other Comprehensive Income	Accumulated Other Comprehensive Income Unrealized gains or losses on our available-for-sale debt securities (after applicable income tax expense or benefit) are included in accumulated other comprehensive income (loss), net ("AOCI"). AOCI is reported in the accompanying consolidated statements of stockholders’ equity and consolidated statements of income and other comprehensive income. GAAP does not permit the adjustment of tax amounts in AOCI for changes in tax rates; as a result the effects become "stranded" in AOCI. Stranded tax effects caused by the 2018 revaluation of deferred taxes resulting from the corporate tax rates established by the Tax Cuts and Jobs Act (the "Tax Act") are reclassified from AOCI to retained earnings in accordance with our early adoption of ASU 2018-02 " Income Statement - Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income."
Cash and Cash Equivalents	Cash and Cash Equivalents Cash equivalents include amounts due from banks, interest-bearing deposits in other banks, federal funds sold and securities purchased under resale agreements.
Investment Securities	Investment Securities Investment securities include debt securities and equity securities at fair value. Debt Securities Debt securities are classified as trading, available-for-sale or held-to-maturity. Management classifies securities at the time of purchase and re-assesses such designation at each balance sheet date; however, transfers between categories from this re-assessment are rare. All debt securities are available-for-sale as of December 31, 2020 and 2019. Trading Account Debt securities acquired for resale in anticipation of short-term market movements are classified as trading, with realized and unrealized gains and losses recognized in income. Held-to-Maturity Debt securities are classified as held-to-maturity when we have the positive intent and ability to hold the securities to maturity. Held-to-maturity securities are stated at amortized cost. Debt securities not classified as held-to-maturity or trading are classified as available-for-sale. Available-for-Sale Available-for-sale debt securities are stated at fair value. Unrealized gains are reported as a separate component of AOCI, net of tax. For available-for-sale debt securities in an unrealized loss position, we first assess whether we intend to sell, or it is more-likely-than-not that we will be required to sell, the securities before recovery of the amortized cost basis. If either of these criteria is met, the securities' amortized cost basis is written down to fair value as a current period expense. If either of the above criteria is not met, we evaluate whether the decline in fair value is the result of credit losses or other factors. In making this assessment, we may consider various factors including the extent to which fair value is less than amortized cost, performance of any underlying collateral and adverse conditions specifically related to the security, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected are compared to the amortized cost basis of the security and any excess of the amortized cost basis over the present value of expected cash flows is recorded as an allowance for credit loss, limited to the amount by which the fair value is less than the amortized cost basis. Any impairment not recorded through an allowance for credit loss is recognized in AOCI, net of tax, as a non credit-related impairment. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity, or in the case of mortgage-backed securities, over the estimated life of the security. Such amortization and accretion are included in interest income from securities. Realized gains and losses and declines in value judged to be other-than-temporary are included in gain (loss) on sale of securities. The cost of securities sold is based on the specific identification method. We have made a policy election to exclude accrued interest from the amortized cost basis of available-for-sale debt securities and report accrued interest separately in accrued interest and other assets in the consolidated balance sheets. Available-for-sale debt securities are placed on non-accrual status when we no longer expect to receive all contractual amounts due, which is generally at 90 days past due. Accrued interest receivable is reversed against interest income when a security is placed on non-accrual status. Accordingly, we do not recognize an allowance for credit loss against accrued interest receivable. Included in debt securities available-for-sale are Credit Risk Transfer ("CRT") securities. CRT securities represent unsecured obligations issued by government sponsored entities ("GSEs") such as Freddie Mac and are designed to transfer mortgage credit risk from the GSE to private investors. CRT securities are structured to be subject to the performance of a reference pool of mortgage loans in which we share in 50% of the first losses with the GSE. If the reference pool incurs losses, the amount we will recover on the notes is reduced by our share of the amount of such losses, which could potentially be up to 100% of the amount outstanding. Unrealized losses recognized in AOCI for the CRT securities are primarily related to the difference between the current market rate for similar securities and the stated interest rate and are not considered to be related to credit loss events. The CRT securities are generally interest-only for an initial period of time and may be restricted from being transferred until a future date. Equity Securities Beginning January 1, 2018, upon adoption of ASU 2016-01 " Recognition and Measurement of Financial Assets and Financial Liabilities," equity securities with readily determinable fair values are stated at fair value with realized and unrealized gains and losses reported in income. For periods prior to January 1, 2018, equity securities were classified as available-for-sale and stated at fair value with unrealized gains and losses reported as a separate component of AOCI, net of tax. Equity securities without readily determinable fair values are recorded at cost less any impairment, if any.
Loans	Loans Loans Held for Sale Through our mortgage correspondent aggregation ("MCA") program, we commit to purchase residential mortgage loans from independent correspondent lenders and deliver those loans into the secondary market via whole loan sales to independent third parties or in securitization transactions to third parties such as Ginnie Mae or to government sponsored entities such as Fannie Mae or Freddie Mac ("GSEs"). In some cases, we retain the mortgage servicing rights. Once purchased, these loans are classified as held for sale and are carried at fair value pursuant to our election of the fair value option in accordance with Accounting Standards Codification ("ASC") 825, Financial Instruments . At the commitment date, we enter into a corresponding forward sale commitment with a third party, typically Ginnie Mae or a GSE, to deliver the loans within a specified timeframe. The estimated gain/loss for the entire transaction (from initial purchase commitment to final delivery of loans) is recorded as an asset or liability. The fair value of loans held for sale is derived from observable current market prices, when available, and includes the fair value of the mortgage servicing rights. Adjustments to reflect unrealized gains and losses resulting from changes in fair value and realized gains and losses upon ultimate sale of the loans are classified as gain/(loss) on sale of loans held for sale in the consolidated statements of income and other comprehensive income. Residential mortgage loans held for sale are subject to both credit and interest rate risk. Credit risk is managed through underwriting policies and procedures, including collateral requirements, which are generally accepted by the secondary loan markets. Exposure to interest rate fluctuations is partially managed through forward sales contracts, which set the price for loans that will be delivered in the next 60 to 90 days. Pursuant to Ginnie Mae servicing guidelines, we have the unilateral right, but not the obligation, to repurchase certain delinquent loans securitized in Ginnie Mae pools, if they meet defined delinquent loan criteria. Once the delinquency criteria have been met, and regardless of whether the repurchase option has been exercised, we account for these loans as if they had been repurchased and recognize the loans and a corresponding liability as held for sale and other liabilities, respectively, in the consolidated balance sheets. If the loans are actually repurchased, the liability is extinguished and the loans continue to be reported as held for sale. As a Ginnie Mae approved lender, we may recover losses incurred on repurchased loans through a claims process with the government agency. From time to time we hold for sale the guaranteed portion of Small Business Administration 7(a) loans, which are carried at lower of cost or market. Loans Held for Investment Loans held for investment (including financing leases) are stated at the amount of unpaid principal reduced by deferred income (net of costs). Interest on loans is recognized using the simple interest method on the daily balances of the principal amounts outstanding. Loan origination fees, net of direct loan origination costs, and commitment fees are deferred and amortized as an adjustment to yield over the life of the loan, or over the commitment period, as applicable. Restructured loans are loans on which, due to the borrower’s financial difficulties, we have granted a concession that we would not otherwise consider for borrowers of similar credit quality. This may include a transfer of real estate or other assets from the borrower, a modification of loan terms, or a combination of the two. Modifications of terms that could potentially qualify as a restructuring include reduction of contractual interest rate, extension of the maturity date at a contractual interest rate lower than the current rate for new debt with similar risk, a reduction of the face amount of debt or forgiveness of either principal or accrued interest. A loan continues to qualify as restructured until a consistent payment history or change in the borrower’s financial condition has been evidenced, generally for no less than twelve months. If the restructuring agreement specifies an interest rate at the time of the restructuring that is greater than or equal to the rate that we are willing to accept for a new extension of credit with comparable risk, then the loan is no longer considered a restructuring if it is in compliance with the modified terms in calendar years after the year of the restructure. A loan is considered past due when a contractually due payment has not been received by the contractual due date. We place a loan on non-accrual when there is a clear indication that the borrower’s cash flow may not be sufficient to meet payments as they become due, which is generally when a loan is 90 days past due. When a loan is placed on non-accrual status, all previously accrued and unpaid interest is reversed as a reduction of current period interest income. Interest income is subsequently recognized on a cash basis as long as the remaining book balance of the asset is deemed to be collectible. If collectability is questionable, then cash payments are applied to principal. A loan is placed back on accrual status when both principal and interest are current and it is probable that we will be able to collect all amounts due (both principal and interest) according to the terms of the loan agreement. Loans held for investment includes legal ownership interests in mortgage loans that we purchase through our mortgage warehouse lending division. The ownership interests are purchased from unaffiliated mortgage originators who are seeking additional funding through sale of the undivided ownership interests to facilitate their ability to originate loans. The mortgage originator has no obligation to offer and we have no obligation to purchase these interests. The originator closes mortgage loans consistent with underwriting standards established by approved investors, and, at the time of the sale to the investor, our ownership interest and that of the originator are delivered by us to the investor selected by the originator and approved by us. We typically purchase up to a 99% ownership interest in each mortgage with the originator owning the remaining percentage. These mortgage ownership interests are generally held by us for a period of less than 30 days and more typically 10-20 days. Because of conditions in agreements with originators designed to reduce transaction risks, under ASC 860, Transfers and Servicing of Financial Assets (“ASC 860”), the ownership interests do not qualify as participating interests. Under ASC 860, the ownership interests are deemed to be loans to the originators and payments we receive from investors are deemed to be payments made by or on behalf of the originator to repay the loan deemed made to the originator. Because we have an actual, legal ownership interest in the underlying residential mortgage loan, these interests are reported as extensions of credit to the originators that are secured by the mortgage loans as collateral. Due to market conditions or events of default by the investor or the originator, we could be required to purchase the remaining interests in the mortgage loans and hold them beyond the expected 10-20 days. Mortgage loans acquired under these conditions would require mark-to-market adjustments to income and could require further allocations of the allowance for credit losses or be subject to charge-off in the event the loans become impaired.
Allowance for Loan Losses	Allowance for Credit Losses The allowance for credit losses is an estimate of the expected credit losses in the loans held for investment and available-for-sale debt securities portfolio. The following is our discussion of the allowance for credit losses on loans held for investment. See "Investment Securities - Available-for-Sale" above for discussion of the allowance for credit losses on available-for-sale debt securities. ASU 2016-13 replaces the incurred loss impairment model, which recognizes losses when it becomes probable that a credit loss will be incurred, with a requirement to recognize lifetime expected credit losses immediately when a financial asset is originated or purchased. The allowance for credit losses is a valuation account that is deducted from the amortized cost basis of loans to present the net amount expected to be collected on the loans. Loans, or portions thereof, are charged off against the allowance when they are deemed uncollectible. Expected recoveries do not exceed the aggregate of amounts previously charged-off and expected to be charged-off. Management estimates the allowance balance using relevant available information, from internal and external sources, relating to past events, current conditions and reasonable and supportable forecasts. Historical credit loss experience provides the basis for the estimation of expected credit losses. Adjustments to historical loss information are made for differences in current loan-specific risk characteristics such as differences in underwriting standards, portfolio mix, credit quality, or term, as well as for changes in macroeconomic conditions, such as changes in unemployment rates, crude oil prices, property values or other relevant factors. The allowance for credit losses is comprised of reserves measured on a collective (pool) basis based on a lifetime loss-rate model when similar risk characteristics exist. Reserves on loans that do not share risk characteristics are evaluated on an individual basis. In order to determine the allowance for credit losses, all loans are assigned a credit grade. Loans graded substandard or worse and greater than $500,000 are specifically reviewed for loss potential and when deemed appropriate are assigned a reserve based on an individual evaluation. For purposes of determining the pool-basis reserve, the remainder of the portfolio, representing all loans not assigned an individual reserve, is segregated first by portfolio segment, then by product type, to recognize differing risk profiles within portfolio segments, and finally by credit grade. Each credit grade within each product type is assigned a historical loss rate. These historical loss rates are then modified to incorporate our reasonable and supportable forecast of future losses at the portfolio segment level, as well as any necessary qualitative adjustments using a Portfolio Level Qualitative Factor ("PLQF") and/or a Portfolio Segment Level Qualitative Factor ("SLQF"). These modified historical loss rates are multiplied by the outstanding principal balance of each loan to calculate a required reserve. A similar process is employed to calculate a reserve assigned to off-balance sheet commitments, specifically unfunded loan commitments and letters of credit, and any needed reserve is recorded in other liabilities. The PLQF and SLQF are utilized to address factors that are not present in historical loss rates and are otherwise unaccounted for in the quantitative process. The PLQF is used to apply a qualitative adjustment across the entire portfolio of loans, while the SLQF is designed to apply a qualitative adjustment across a single portfolio segment. Even though portions of the allowance may be allocated to specific loans, the entire allowance is available for any credit that, in management’s judgment, should be charged off. We generally use a two-year forecast period, based on a single consensus forecast scenario, using variables we believe are most relevant to each portfolio segment. For periods beyond which we are able to develop reasonable and supportable forecasts, we immediately revert to the average historical loss rate. The forecast period and scenario used is reviewed on a quarterly basis and may be adjusted based on management's view of the current economic conditions and level of predictability the forecast can provide. Portfolio segments are used to pool loans with similar risk characteristics and align with our methodology for measuring expected credit losses. A summary of our primary portfolio segments is as follows: Commercial . Our commercial loan portfolio is comprised of lines of credit for working capital, term loans and leases to finance equipment and other business assets across a variety of industries. These loans are used for general corporate purposes including financing working capital, internal growth, acquisitions and business insurance premiums and are generally secured by accounts receivable, inventory, equipment and other assets of our clients’ businesses. Our commercial loan portfolio also includes consumer loans because our small portfolio of consumer loans is largely comprised of accommodation loans to individuals associated with our commercial clients. Energy . Our energy loan portfolio is primarily comprised of loans to exploration and production (“E&P”) companies that are generally collateralized with proven reserves based on appropriate valuation standards that take into account the risk of oil and gas price volatility. The majority of this portfolio is first lien, senior secured, reserve-based lending, which we believe is the lowest-risk form of energy lending. Energy loans are impacted by commodity price volatility, as well as changes in consumer and business demand. Mortgage finance . Mortgage finance loans relate to our mortgage warehouse lending operations in which we purchase mortgage loan ownership interests from unaffiliated mortgage originators that are generally held by us for a period of less than 30 days and more typically 10-20 days before they are sold to an approved investor. Volumes fluctuate based on the level of market demand for the product and the number of days between purchase and sale of the loans, which can be affected by changes in overall market interest rates and housing demand and tend to peak at the end of each month. Mortgage finance loans are consistently underwritten based on standards established by the approved investors. Market conditions or events of default by an investor or originator could require that we repurchase the remaining interests in the mortgage loans and hold them beyond the expected 10-20 days. Real estate . Our real estate portfolio is comprised of the following types of loans: Commercial real estate ("CRE") . Our CRE portfolio is comprised of both construction/development financing and limited term financing provided to professional real estate developers and owners/managers of commercial real estate projects and properties who have a demonstrated record of past success with similar properties. Collateral properties include office buildings, warehouse/distribution buildings, shopping centers, hotels/motels, senior living, apartment buildings and residential and commercial tract development. The primary source of repayment on these loans is expected to come from the sale, permanent financing or lease of the real property collateral. CRE loans are impacted by fluctuations in collateral values, as well as the ability of the borrower to obtain permanent financing. Residential homebuilder finance ("RBF") . The RBF portfolio is comprised of loans made to residential builders and developers. Loans to residential builders are typically in the form of uncommitted guidance lines and are for the purpose of developing lots into single-family homes, while loans to developers are typically in the form of borrowing base lines extended for the purpose of acquiring and developing raw land into lots that can be further sold to home builders. RBF loans, if not structured and monitored correctly, can be impacted by volatility in consumer demand, as well as fluctuation in housing prices. Secured by 1-4 family . This category of loans includes both first and second lien loans made for the purpose of purchasing or constructing 1-4 family residential dwellings, as well as home equity revolving lines of credit and loans to purchase lots for future construction of 1-4 family residential dwellings. Other . The "other" category is primarily comprised of real estate loans originated through a Small Business Administration (SBA) program where repayment is partially guaranteed by the SBA, as well as other loans secured by real estate where the primary source of repayment is not expected to come from the sale or lease of the real property collateral. We have several pass credit grades that are assigned to loans based on varying levels of risk, ranging from credits that are secured by cash or marketable securities, to watch credits which have all the characteristics of an acceptable credit risk but warrant more than the normal level of monitoring. Within our criticized/classified credit grades are special mention, substandard and doubtful. Special mention loans are those that are currently protected by the sound worth and paying capacity of the borrower, but that are potentially weak and constitute an additional credit risk. These loans have the potential to deteriorate to a substandard grade due to the existence of financial or administrative deficiencies. Substandard loans have a well-defined weakness or weaknesses that jeopardizes the liquidation of the debt. They are characterized by the distinct possibility that we will sustain some loss if the deficiencies are not corrected. Some substandard loans are inadequately protected by the sound worth and paying capacity of the borrower and of the collateral pledged and may be considered impaired. Substandard loans can be accruing or can be on non-accrual depending on the circumstances of the individual loans. Loans classified as doubtful have all the weaknesses inherent in substandard loans with the added characteristics that the weaknesses make collection in full highly questionable and improbable. The possibility of loss is extremely high. All doubtful loans are on non-accrual. The methodology used in the estimation of the allowance, which is performed at least quarterly, is designed to be dynamic and responsive to changes in portfolio credit quality and forecasted economic conditions. Changes are reflected in the pool-basis allowance and in reserves assigned on an individual basis as the collectability of classified loans is evaluated with new information. As our portfolio has matured, historical loss ratios have been closely monitored. The review of the appropriateness of the allowance is performed by executive management and presented to the audit and risk committees of our board of directors for their review. The committees report to the board as part of the board's review on a quarterly basis of our consolidated financial statements. When management determines that foreclosure is probable, and for certain collateral-dependent loans where foreclosure is not considered probable, expected credit losses are based on the estimated fair value of the collateral adjusted for selling costs, when appropriate. A loan is considered collateral-dependent when the borrower is experiencing financial difficulty and repayment is expected to be provided substantially through the operation or sale of the collateral. Expected credit losses are estimated over the contractual term of the loans, adjusted for expected prepayments when appropriate. The contractual term excludes expected extensions, renewals and modifications unless either of the following applies: management has a reasonable expectation that a loan will be restructured, or the extension or renewal options are included in the borrower contract and are not unconditionally cancellable by us. We do not measure an allowance for credit losses on accrued interest receivable balances because these balances are written off in a timely manner as a reduction to interest income when loans are placed on non-accrual status as discussed above.
Other Real Estate Owned	Other Real Estate Owned Other real estate owned (“OREO”), which is included in other assets on the consolidated balance sheet, consists of real estate that has been foreclosed. When foreclosure occurs, the acquired asset is recorded at fair value less selling costs, generally based on appraised value, which may result in partial charge-off of the loan through a charge to the allowance for credit losses, if necessary. Subsequent write-downs required for declines in value are recorded through a valuation allowance, or taken directly to the asset, and are recorded in allowance and other carrying costs for OREO in the consolidated statements of income and other comprehensive income. Gains or losses on sale of OREO are recorded in other non-interest income in the consolidated statements of income and other comprehensive income.
Mortgage Servicing Rights	Mortgage Servicing Rights, Net Mortgage servicing rights ("MSRs") are created by selling mortgage loans with servicing rights retained. We identify classes of servicing rights based upon the nature of the underlying assumptions used to value the asset along with the risks associated with the underlying asset. Based upon these criteria we have one class of MSRs, residential. MSRs are recognized based on the estimated fair value of the mortgage loans and the related servicing rights at the date of sale using values derived from a valuation model. MSRs are reported on the consolidated balance sheets at amortized cost, less a valuation allowance if the fair value of identified strata within the MSR portfolio are determined to have a fair value that is less than amortized cost. MSRs are amortized proportionally over the estimated life of the projected net servicing revenue and are periodically evaluated for impairment. Loan servicing fee income represents income earned for servicing mortgage loans owned by investors and includes mortgage servicing fees and other ancillary servicing income. Servicing fees are recorded as income when earned and are reported in non-interest income on the consolidated statements of income and other comprehensive income. MSR valuation allowance expense and servicing related expenses are recorded in servicing-related expenses in the consolidated statements of income and other comprehensive income. The estimated fair value of the MSR assets is obtained from an independent third party and reviewed by management on a quarterly basis. MSRs typically do not trade in an active, open market with readily observable prices; as such, the fair value of MSRs is determined using a discounted cash flow model to calculate the present value of the estimated future net servicing income. The assumptions utilized in the discounted cash flow model are based on market data for comparable assets, where available. Each quarter, management and the independent third party review the key assumptions used in the discounted cash flow model and make adjustments as necessary to estimate the fair value of the MSRs.
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets, Net Intangible assets are acquired assets that lack physical substance but can be distinguished from goodwill because of contractual or other legal rights or because the asset is capable of being sold or exchanged either on its own or in combination with a related contract, asset or liability. Our intangible assets relate primarily to loan customer relationships purchased as part of business acquisitions. Intangible assets with definite useful lives are amortized over their estimated life. Goodwill and intangible assets are tested for impairment at least annually or whenever changes in circumstances indicate the carrying amount of the assets may not be recoverable from future undiscounted cash flows. If impaired, the assets are recorded at fair value.
Premises and Equipment	Premises and Equipment, Net Premises and equipment are stated at cost less accumulated depreciation. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Furniture and equipment is generally depreciated over three
Software	Software Costs incurred in connection with development or purchase of internal use software and cloud computing arrangements, including in-substance software licenses, are capitalized. Amortization is computed on a straight-line basis over the estimated useful life of the asset, which generally ranges from one
Financial Instruments with Off-Balance Sheet Risk	Financial Instruments with Off-Balance Sheet Risk The Company has undertaken certain guarantee obligations in the ordinary course of business which include liabilities with off-balance sheet risk. We consider the following arrangements to be guarantees: commitments to extend credit, standby letters of credit and indemnification agreements included within third party contractual arrangements. The Bank is a party to financial instruments with off-balance sheet risk in the normal course of business to meet the financing needs of its customers. These financial instruments include commitments to extend credit and standby letters of credit that involve varying degrees of credit risk in excess of the amount recognized in the consolidated balance sheets. The Bank’s exposure to credit loss in the event of non-performance by the other party to the financial instrument for commitments to extend credit and standby letters of credit is represented by the contractual amount of these instruments. The Bank uses the same credit policies in making commitments and conditional obligations as it does for on-balance sheet instruments. The amount of collateral obtained, if deemed necessary, is based on management’s credit evaluation of the borrower. Commitments to extend credit are agreements to lend to a customer as long as there is no violation of any condition established in the contract. Commitments generally have fixed expiration dates or other termination clauses and may require payment of a fee. Since many of the commitments may expire without being drawn upon, the total commitment amounts do not necessarily represent future cash requirements. The Bank evaluates each customer’s creditworthiness on a case-by-case basis. Standby letters of credit are conditional commitments issued by the Bank to guarantee the performance of a customer to a third party. Those guarantees are primarily issued to support public and private borrowing arrangements. The credit risk involved in issuing letters of credit is essentially the same as that involved in extending loan facilities to customers. In conjunction with the sale and securitization of loans held for sale and their related servicing rights, we may be exposed to liability resulting from recourse, repurchase and make-whole agreements. If it is determined subsequent to our sale of a loan or its related servicing rights that a breach of the representations or warranties made in the applicable sale agreement has occurred, which may include guarantees that prepayments will not occur within a specified and customary time frame, we may have an obligation to either (a) repurchase the loan for the unpaid principal balance, accrued interest and related advances, (b) indemnify the purchaser against any loss it suffers or (c) make the purchaser whole for the economic benefits of the loan and its related servicing rights. Our repurchase, indemnification and make-whole obligations vary based upon the terms of the applicable agreements, the nature of the asserted breach and the status of the mortgage loan at the time a claim is made. We establish reserves for estimated losses of this nature inherent in the origination of mortgage loans by estimating the losses inherent in the population of all loans sold based on trends in claims and actual loss severities experienced. The reserve will include accruals for probable contingent losses in addition to those identified in the pipeline of claims received. The estimation process is designed to include amounts based on actual losses experienced from actual activity.
Leases	Leases ASU 2016-02 "Leases (Topic 842)" ("ASU 2016-02") requires that lessees and lessors recognize lease assets and lease liabilities on the balance sheet and disclose key information about leasing arrangements. ASU 2016-02 became effective for us on January 1, 2019. ASU 2016-02 provides for a modified retrospective transition approach requiring lessees to recognize and measure leases on the balance sheet at the beginning of either the earliest period presented or as of the beginning of the period of adoption with the option to elect certain practical expedients. We elected to apply ASU 2016-02 as of the beginning of the period of adoption (January 1, 2019) and have not restated comparative periods. Of the optional practical expedients available under ASU 2016-02, we adopted all expedients except for the hindsight practical expedient. As a result of implementing ASU 2016-02, we recognized an operating lease right-of-use ("ROU") asset of $64 million and an operating lease liability of $74 million on January 1, 2019, with no impact on our consolidated statements of income or consolidated statements of cash flows compared to the prior lease accounting model. Operating lease ROU assets represent our right to use an underlying asset during the lease term and operating lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease agreements may contain extension options which typically range from 5 to 10 years at the then fair market rental rates. As these extension options are not generally considered reasonably certain of exercise, they are not included in the lease term. ROU assets and operating lease liabilities are recognized at lease commencement based on the present value of the remaining lease payments using a discount rate that represents our incremental borrowing rate at the lease commencement date, which is based on our collateralized borrowing capabilities over a similar term as the related lease payments. ROU assets are further adjusted for lease incentives. Our operating leases relate primarily to office space and bank branches. Operating leases in which we are the lessee are recorded as operating lease ROU assets and operating lease liabilities, included in other assets and other liabilities, respectively, on our consolidated balance sheets. Operating lease expense, which is comprised of amortization of the ROU asset and the implicit interest accreted on the operating lease liability, is recognized on a straight-line basis over the lease term, and is recorded in net occupancy expense in the consolidated statements of income and other comprehensive income. See Note 6 – Leases for additional information.
Revenue Recognition	Revenue Recognition ASC 606, Revenue from Contracts with Customers ("ASC 606"), establishes principles for reporting information about the nature, amount, timing and uncertainty of revenue and cash flows arising from the entity's contracts to provide goods or services to customers. The core principle requires an entity to recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration that it expects to be entitled to receive in exchange for those goods or services recognized as performance obligations are satisfied. The majority of our revenue-generating transactions are not subject to ASC 606, including revenue generated from financial instruments, such as our loans, letters of credit, derivatives and investment securities, as well as revenue related to our mortgage servicing activities, as these activities are subject to other GAAP discussed elsewhere within our disclosures. Descriptions of our revenue-generating activities that are within the scope of ASC 606, which are presented in our income statements as components of non-interest income are as follows: • Service charges on deposit accounts - these represent general service fees for monthly account maintenance and activity- or transaction-based fees and consist of transaction-based revenue, time-based revenue (service period), item-based revenue or some other individual attribute-based revenue. Revenue is recognized when our performance obligation is completed, which is generally monthly for account maintenance services or when a transaction has been completed (such as a wire transfer). Payments for such performance obligations are generally received at the time the performance obligations are satisfied. • Wealth management and trust fee income - this represents monthly fees due from wealth management customers as consideration for managing the customers' assets. Wealth management and trust services include custody of assets, investment management, escrow services, fees for trust services and similar fiduciary activities. Revenue is recognized when our performance obligation is completed each month, which is generally the time that payment is received. Also included are fees received from a third party broker-dealer as part of a revenue-sharing agreement for fees earned from customers that we refer to the third party. These fees are paid to us by the third party on a quarterly basis and recognized ratably throughout the quarter as our performance obligation is satisfied. • Brokered loan fees - these represent fees for the administration and funding of purchased mortgage loan interests as well as facility renewal and application fees received from mortgage originator customers in our mortgage warehouse lending business. Also included are fees received from independent correspondent mortgage lenders as consideration for our purchase of individual residential mortgage loans through our MCA business. Revenue related to the mortgage warehouse lending business is recognized when the related loan interest is disposed (i.e., through sale or payoff) or upon receipt of the facility renewal or application. Revenue related to our MCA business is recognized at the time a loan is purchased. • Other non-interest income primarily includes items such as letter of credit fees, bank owned life insurance income, dividends on FHLB and FRB stock and other general operating income, none of which are subject to the requirements of ASC 606.
Stock-based Compensation	Stock-based Compensation We account for all stock-based compensation transactions in accordance with ASC 718, Compensation — Stock Compensation (“ASC 718”), which requires that stock compensation transactions be recognized as compensation expense in the consolidated statements of income and other comprehensive income based on their fair values on the measurement date, which is the date of the grant.
Income Taxes	Income Taxes The Company and its subsidiary file a consolidated federal income tax return. We utilize the liability method in accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based upon the difference between the values of the assets and liabilities as reflected in the financial statements and their related tax basis using enacted tax rates in effect for the year in which the differences are expected to be recovered or settled. As changes in tax law or rates are enacted, deferred tax assets and liabilities are adjusted through the provision for income taxes. A valuation allowance is provided against deferred tax assets unless it is more likely than not that such deferred tax assets will be realized. Unrecognized tax benefits for the uncertain portion of recorded tax benefits and related interest may result from the application of complex tax laws, rules, regulations and interpretations. Unrecognized tax benefits, as well as estimated penalties and interest, are assessed quarterly and may be adjusted through current income tax expense in future periods based on changing facts and circumstances, completion of examinations by taxing authorities or expiration of a statute of limitations.
Fair Values of Financial Instruments	Fair Values of Financial Instruments ASC 820, Fair Value Measurements and Disclosures (“ASC 820”), defines fair value, establishes a framework for measuring fair value under GAAP and enhances disclosures about fair value measurements. The standard describes three levels of inputs that may be used to measure fair value as provided below. Level 1 Quoted prices in active markets for identical assets or liabilities. Level 2 Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Level 3 assets and liabilities include financial instruments whose value is determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair values requires significant management judgment or estimation. Also required are disclosures of fair value information about financial instruments, whether or not recognized on the balance sheet, for which it is practical to estimate that value. In cases where quoted market prices are not available, fair values are based on estimates using present value or other valuation techniques. Those techniques are significantly affected by the assumptions used, including the discount rate and estimates of future cash flows. The disclosure of fair value information about financial instruments does not and is not intended to represent the fair value of the Company. The following are descriptions of the methods and significant assumptions used by the Company in estimating its fair value disclosures for financial instruments: Cash and Cash Equivalents, Variable Rate Loans, and Variable Rate Debt The fair value of these financial instruments approximates carrying value. Investment Securities Within the investment securities portfolio, we hold equity securities related to our non-qualified deferred compensation plan that are valued using quoted market prices for identical equity securities in an active market, and are classified as Level 1 assets in the fair value hierarchy. We also hold Community Reinvestment Act equity securities that are valued using quoted market prices for identical equity securities in an inactive market that we classify as Level 2 assets in the fair value hierarchy. The fair value of our U.S. government agency and residential mortgage-backed securities are based on prices obtained from independent pricing services that are based on quoted market prices for the same or similar securities, and are characterized as Level 2 assets in the fair value hierarchy. We obtain documentation from our primary pricing service regarding their processes and controls applicable to pricing investment securities, and on a quarterly basis independently verify the prices that we receive from the service provider using two additional independent pricing sources. We also hold tax-exempt asset-backed securities and CRT securities that are valued using a discounted cash flow model, which utilizes Level 3 inputs, and are classified as Level 3 assets in the fair value hierarchy. Loans Held for Sale The fair value for loans held for sale is derived from quoted market prices for similar loans, in which case they are characterized as Level 2 assets in the fair value hierarchy, or is derived from third party pricing models, in which case they are characterized as Level 3 assets in the fair value hierarchy. Derivative Assets and Liabilities The estimated fair value of interest rate swaps and caps is obtained from independent pricing services based on quoted market prices for similar derivative contracts and these financial instruments are characterized as Level 2 assets and liabilities in the fair value hierarchy. On a quarterly basis, we independently verify the fair value using an additional independent pricing source. Foreign currency forward contracts are valued based upon quoted market prices obtained from independent pricing services for similar derivative contracts. As such, these financial instruments are characterized as Level 2 assets and liabilities in the fair
Derivative Financial Instruments	Derivative Financial Instruments All contracts that satisfy the definition of a derivative are recorded at fair value in other assets and other liabilities in the consolidated balance sheets. We record the derivatives on a net basis when a right of offset exists with a single counterparty that is subject to a legally enforceable master netting agreement. We enter into interest rate derivative contracts that are not designated as hedging instruments. These derivative positions relate to transactions in which we enter into an interest rate swap, cap and/or floor with a customer while at the same time entering into an offsetting interest rate swap, cap and/or floor with another financial institution. In connection with each swap transaction, we agree to pay interest to the customer on a notional amount at a variable interest rate and receive interest from the customer on a similar notional amount at a fixed interest rate. At the same time, we agree to pay another financial institution the same fixed interest rate on the same notional amount and receive the same variable interest rate on the same notional amount. The transaction allows our customer to effectively convert a variable rate loan to a fixed rate. Because we act as an intermediary for our customer, changes in the fair value of the underlying derivative contracts substantially offset each other and do not have a material impact on our results of operations. We also enter into foreign currency forward contracts that are not designateed as hedging instruments. These derivative instruments relate to transactions in which we enter into a contract with a customer to buy or sell a foreign currency at a future date for a specified price while at the same time entering into an offsetting contract with a financial institution to buy or sell the same currency at the same future date for a specified price. These transactions allow our customers to manage their exposure to foreign currency exchange rate fluctuations. Because we act as an intermediary for our customer, changes in the fair value of the underlying derivative instruments substantially offset each other and do not have a material impact on our results of operations. As part of our MCA program, we enter into loan purchase commitment contracts with mortgage originators to purchase residential mortgage loans at a future date, as well as forward sales commitment contracts to sell residential mortgage loans or to deliver mortgage-backed securities at a future date. The objective of these transactions is to mitigate our exposure to interest rate risk associated with the purchase of mortgage loans held for sale. Any changes in fair value are recorded in gain/(loss) on sale of loans held for sale in the consolidated statements of income and other comprehensive income. To mitigate exposure to potential impairment losses from adverse changes in the fair value of our residential MSR portfolio, we enter into interest rate derivative contracts, primarily interest rate swap futures and forward sale commitments of mortgage-backed securities. These derivative instruments are considered highly liquid and can be settled daily, which allows us to dynamically manage our exposure. The derivative instruments are used to economically hedge the fair value of the residential MSR portfolio impacted by changes in anticipated prepayments resulting from mortgage interest rate movements and are classified as other assets and other liabilities on the consolidated balance sheets. Any unrealized or realized gains/(losses) related to derivatives economically hedging the residential MSR portfolio are recognized in servicing-related expenses along with changes to the MSR valuation allowance.
Segment Reporting	Segment Reporting We have determined that all of our lending divisions and subsidiaries meet the aggregation criteria of ASC 280, Segment Reporting , since all offer similar products and services, operate with similar processes, have similar customers and are collectively reviewed by the chief operating decision maker.

Operations and Summary of Sig_3

Operations and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Schedule of Error Corrections and Prior Period Adjustments	A summary of revisions to certain previously reported financial information is presented below: Revised Consolidated Balance Sheets December 31, 2019 December 31, 2018 December 31, 2017 ( in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Other liabilities $ 287,157 $ 30,937 $ 318,094 $ 194,238 $ 20,086 $ 214,324 $ 182,212 $ 12,649 $ 194,861 Total liabilities 29,715,811 30,937 29,746,748 25,757,373 20,086 $ 25,777,459 22,872,924 12,649 22,885,573 Retained Earnings 1,694,608 (30,937) 1,663,671 1,381,492 (20,086) $ 1,361,406 1,090,500 (12,649) 1,077,851 Total Equity 2,832,258 (30,937) 2,801,321 2,500,394 (20,086) $ 2,480,308 2,202,721 (12,649) 2,190,072 Revised Consolidated Statement of Income and Other Comprehensive Income Year Ended December 31, 2019 Year Ended December 31, 2018 Year Ended December 31, 2017 (in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Salaries and employee benefits expense $ 315,080 $ 13,403 $ 328,483 $ 291,768 $ 9,131 $ 300,899 $ 264,231 $ 2,230 $ 266,461 Other non-interest expense 47,253 (2,552) 44,701 51,364 (1,694) 49,670 49,296 (1,248) 48,048 Total non-interest expense 589,999 10,851 600,850 525,096 7,437 532,533 465,876 982 466,858 Income before tax 407,161 (10,851) 396,310 380,788 (7,437) 373,351 325,708 (982) 324,726 Net income 322,866 (10,851) 312,015 300,824 (7,437) 293,387 197,063 (982) 196,081 Net income available to common stockholders 313,116 (10,851) 302,265 291,074 (7,437) 283,637 187,313 (982) 186,331 Comprehensive income 331,298 (10,851) 320,447 300,830 (7,437) 293,393 197,076 (982) 196,094 Revised Consolidated Statement of Stockholders' Equity Year Ended December 31, 2019 Year Ended December 31, 2018 Year Ended December 31, 2017 (in thousands) As Reported Adjustment As Revised As Reported Adjustment As Revised As Reported Adjustment As Revised Beginning balance retained earnings $ 1,381,492 $ (20,086) $ 1,361,406 $ 1,090,500 $ (12,649) $ 1,077,851 $ 903,187 $ (11,667) $ 891,520 Beginning balance total equity 2,500,394 (20,086) 2,480,308 2,202,721 (12,649) 2,190,072 2,009,557 (11,667) 1,997,890 Ending balance retained earnings 1,694,608 (30,937) 1,663,671 1,381,492 (20,086) 1,361,406 1,090,500 (12,649) 1,077,851 Ending balance total equity 2,832,258 (30,937) 2,801,321 2,500,394 (20,086) 2,480,308 2,202,721 (12,649) 2,190,072
Accounting Standards Update and Change in Accounting Principle	The following table illustrates the impact of adopting ASU 2016-13 and details how outstanding loan balances have been reclassified as a result of changes made to our primary portfolio segments under CECL: January 1, 2020 (in thousands) As Reported Under ASU 2016-13 Pre-ASU 2016-13 Impact of ASU 2016-13 Adoption Assets: Loans held for investment (outstanding balance) Commercial $ 9,133,444 $ 10,230,828 $ (1,097,384) Energy 1,425,309 1,425,309 Mortgage finance 8,169,849 8,169,849 — Construction 2,563,339 (2,563,339) Real estate 6,008,040 3,444,701 2,563,339 Consumer 71,463 (71,463) Equipment leases 256,462 (256,462) Allowance for credit losses on loans (203,632) (195,047) (8,585) Total loans held for investment, net 24,442,630 24,451,215 (8,585) Net deferred tax asset 23,058 21,064 1,994 Liabilities: Allowance for credit losses on off-balance sheet exposures 9,203 8,640 563 Equity: Retained earnings 1,656,517 1,663,671 (7,154)

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of computation of basic and diluted earnings per share	The following table presents the computation of basic and diluted earnings per share: Year ended December 31, (in thousands except per share data) 2020 2019 2018 Numerator: Net income $ 66,289 $ 312,015 $ 293,387 Preferred stock dividends 9,750 9,750 9,750 Net income available to common stockholders $ 56,539 $ 302,265 $ 283,637 Denominator: Denominator for basic earnings per share—weighted average shares 50,430,326 50,286,300 49,936,702 Effect of employee stock-based awards(1) 152,653 132,904 218,275 Effect of warrants to purchase common stock — — 117,895 Denominator for dilutive earnings per share—adjusted weighted average shares and assumed conversions 50,582,979 50,419,204 50,272,872 Basic earnings per common share $ 1.12 $ 6.01 $ 5.68 Diluted earnings per common share $ 1.12 $ 5.99 $ 5.64 (1) SARs and RSUs outstanding of 453,024, 86,308 and 27,100 in 2020, 2019 and 2018, respectively, have not been included in diluted earnings per share because to do so would have been antidilutive for the periods presented.

Investment Securities (Tables)

Investment Securities (Tables)	12 Months Ended
	Dec. 31, 2020
Investments, Debt and Equity Securities [Abstract]
Summary of securities	The following is a summary of available-for-sale debt securities: (in thousands) Amortized Gross Gross Estimated December 31, 2020 U.S. government agency securities $ 125,000 $ 1 $ (1,412) $ 123,589 Residential mortgage-backed securities 2,818,518 11,566 (1,128) 2,828,956 Tax-exempt asset-backed securities 184,940 14,236 — 199,176 Credit risk transfer securities 14,713 — (3,296) 11,417 Total $ 3,143,171 $ 25,803 $ (5,836) $ 3,163,138 December 31, 2019 Residential mortgage-backed securities $ 4,991 $ 275 $ — $ 5,266 Tax-exempt asset-backed securities 183,225 13,802 — 197,027 Credit risk asset-backed securities 14,713 — (2,749) 11,964 Total $ 202,929 $ 14,077 $ (2,749) $ 214,257 (1) Excludes accrued interest receivable of $6.0 million and $1.6 million at December 31, 2020 and 2019, respectively, that is recorded in accrued interest receivable and other assets.
Schedule of amortized cost and estimated fair value of securities	The amortized cost and estimated fair value, excluding accrued interest receivable, and weighted average yield of available-for-sale debt securities are presented below by contractual maturity: (in thousands, except percentage data) Less Than After One After Five After Ten Total December 31, 2020 U.S. government agency securities:(1) Amortized cost $ — $ — $ 125,000 $ — $ 125,000 Estimated fair value — — 123,589 — 123,589 Weighted average yield(3) — % — % 1.13 % — % 1.13 % Residential mortgage-backed securities:(1) Amortized cost $ — $ 545 $ 17,500 $ 2,800,473 $ 2,818,518 Estimated fair value — 605 17,490 2,810,861 2,828,956 Weighted average yield(3) — % 4.58 % 1.08 % 1.25 % 1.25 % Tax-exempt asset-backed securities:(1) Amortized Cost — — — 184,940 184,940 Estimated fair value — — — 199,176 199,176 Weighted average yield(2)(3) — % — % — % 4.92 % 4.92 % CRT securities:(1) Amortized Cost — — — 14,713 14,713 Estimated fair value — — — 11,417 11,417 Weighted average yield(3) — % — % — % 0.15 % 0.15 % Total available-for-sale debt securities: Amortized cost $ 3,143,171 Estimated fair value $ 3,163,138 December 31, 2019 Residential mortgage-backed securities:(1) Amortized cost $ — $ 1,005 $ — $ 3,986 $ 4,991 Estimated fair value — 1,088 — 4,178 5,266 Weighted average yield(3) — % 5.54 % — % 4.31 % 4.55 % Tax-exempt asset-backed securities:(1) Amortized Cost — — — 183,225 183,225 Estimated fair value — — — 197,027 197,027 Weighted average yield(2)(3) — % — % — % 5.32 % 5.32 % CRT securities:(1) Amortized Cost — — — 14,713 14,713 Estimated fair value — — — 11,964 11,964 Weighted average yield(3) — % — % — % 1.71 % 1.71 % Total available-for-sale debt securities: Amortized cost $ 202,929 Estimated fair value $ 214,257 (1) Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without prepayment penalties. (2) Yields have been adjusted to a tax equivalent basis assuming a 21% federal tax rate. (3) Yields are calculated based on amortized cost.
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	The following table discloses our available-for-sale debt securities that have been in a continuous unrealized loss position for less than 12 months and those that have been in a continuous unrealized loss position for 12 or more months: Less Than 12 Months 12 Months or Longer Total (in thousands) Fair Value Unrealized Loss Fair Value Unrealized Loss Fair Value Unrealized Loss December 31, 2020 U.S. government agency securities $ 98,588 $ (1,412) $ — $ — $ 98,588 $ (1,412) Residential mortgage-backed securities 354,387 (1,128) — — 354,387 (1,128) CRT securities — — 11,417 (3,296) 11,417 (3,296) Total $ 452,975 $ (2,540) $ 11,417 $ (3,296) $ 464,392 $ (5,836) December 31, 2019 CRT securities $ 11,964 $ (2,749) $ — $ — $ 11,964 $ (2,749) Total $ 11,964 $ (2,749) $ — $ — $ 11,964 $ (2,749)
Summary of unrealized and realized gains/(losses) recognized in net income on equity securities	The following is a summary of unrealized and realized gains/(losses) recognized on equity securities and included in other non-interest income in the consolidated statements of income: Year Ended December 31, (in thousands) 2020 2019 Net gains/(losses) recognized during the period $ 2,998 $ 2,383 Less: Realized net gains/(losses) recognized during the period on equity securities sold 1,418 119 Unrealized net gains/(losses) recognized during the period on equity securities still held $ 1,580 $ 2,264

Loans Held for Investment and_2

Loans Held for Investment and Allowance for Loan Losses (Tables)	12 Months Ended
	Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable, Gross, Allowance, and Net [Abstract]
Schedule of loans held for investments	Loans held for investment are summarized by portfolio segment as follows: December 31, (in thousands) 2020 2019 Commercial $ 8,861,580 $ 9,133,444 Energy 766,217 1,425,309 Mortgage finance(1) 9,079,409 8,169,849 Real estate 5,794,624 6,008,040 Gross loans held for investment(2) 24,501,830 24,736,642 Deferred income (net of direct origination costs) (70,970) (90,380) Allowance for credit losses on loans (254,615) (195,047) Total loans held for investment, net(2) $ 24,176,245 $ 24,451,215 (1) Balances at December 31, 2020 and December 31, 2019 are stated net of $1.2 billion and $682.7 million of participations sold, respectively. (2) Excludes accrued interest receivable of $56.5 million and $63.4 million at December 31, 2020 and December 31, 2019, respectively, that is recorded in accrued interest receivable and other assets.
Schedule of the credit risk profile of loan portfolio by internally assigned grades and nonaccrual status	The following table summarizes our gross loans held for investment by year of origination and internally assigned credit grades: (in thousands) 2020 2019 2018 2017 2016 2015 and prior Revolving lines of credit Revolving lines of credit converted to term loans Total December 31, 2020 Commercial (1-7) Pass $ 1,259,949 $ 2,816,425 $ 543,438 $ 374,455 $ 192,060 $ 213,212 $ 3,020,353 $ 40,253 $ 8,460,145 (8) Special mention 2,664 115,015 38,751 26,423 1,983 290 19,971 22,797 227,894 (9) Substandard - accruing 15,773 15,854 18,068 32,241 15,297 19,639 22,932 1,641 141,445 (9+) Non-accrual 1,820 8,360 377 1,292 802 15,157 3,836 452 32,096 Total commercial $ 1,280,206 $ 2,955,654 $ 600,634 $ 434,411 $ 210,142 $ 248,298 $ 3,067,092 $ 65,143 $ 8,861,580 Energy (1-7) Pass $ — $ 12,020 $ 7,598 $ 26,931 $ — $ 23,750 $ 553,970 $ — $ 624,269 (8) Special mention — — — — — 13,358 76,866 — 90,224 (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — 5,705 1,972 8,009 36,038 — 51,724 Total energy $ — $ 12,020 $ 7,598 $ 32,636 $ 1,972 $ 45,117 $ 666,874 $ — $ 766,217 Mortgage finance (1-7) Pass $ 755,309 $ 1,063,641 $ 821,122 $ 483,436 $ 106,013 $ 5,849,888 $ — $ — $ 9,079,409 (8) Special mention — — — — — — — — — (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — — — — — — — Total mortgage finance $ 755,309 $ 1,063,641 $ 821,122 $ 483,436 $ 106,013 $ 5,849,888 $ — $ — $ 9,079,409 Real estate CRE (1-7) Pass $ 352,688 $ 892,831 $ 923,762 $ 444,587 $ 208,426 $ 451,283 $ 62,336 $ 61,133 $ 3,397,046 (8) Special mention 3,475 11,170 6,485 88,633 11,153 17,623 — 1,247 139,786 (9) Substandard - accruing — 327 47,708 11,601 32,645 30,766 — 15,940 138,987 (9+) Non-accrual — — — — 5,749 4,852 — — 10,601 RBF (1-7) Pass 162,397 60,077 65,271 3,727 5,888 8,483 551,703 — 857,546 (8) Special mention — 353 — — — — — — 353 (9) Substandard - accruing — — — — — — — — — (9+) Non-accrual — — — — — — — — — Other (1-7) Pass 190,995 150,787 119,696 120,817 82,465 113,105 16,630 39,129 833,624 (8) Special mention — 6,700 2,240 — 1,843 7,195 — 1,018 18,996 (9) Substandard - accruing — — 2,567 14,452 3,301 14,453 — — 34,773 (9+) Non-accrual — — — 927 5,524 6,403 — 14,496 27,350 Secured by 1-4 family (1-7) Pass 58,515 63,031 46,623 54,096 72,527 31,880 4,697 — 331,369 (8) Special mention 646 — — 635 — 1,768 — — 3,049 (9) Substandard - accruing — — — 817 — 109 — — 926 (9+) Non-accrual — — — — — 218 — — 218 Total real estate $ 768,716 $ 1,185,276 $ 1,214,352 $ 740,292 $ 429,521 $ 688,138 $ 635,366 $ 132,963 $ 5,794,624 Total loans held for investment $ 2,804,231 $ 5,216,591 $ 2,643,706 $ 1,690,775 $ 747,648 $ 6,831,441 $ 4,369,332 $ 198,106 $ 24,501,830
Schedule of activity in the reserve for loan losses by portfolio segment	The following table details activity in the allowance for credit losses on loans. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. (in thousands) Commercial Energy Mortgage Real Additional Qualitative Reserve Total Year ended December 31, 2020 Beginning balance $ 102,254 $ 60,253 $ 2,265 $ 30,275 $ — $ 195,047 Impact of CECL adoptions (15,740) 24,154 2,031 (1,860) — 8,585 Provision for credit losses on loans 58,630 126,180 403 64,556 — 249,769 Charge-offs 73,360 133,522 — 180 — 207,062 Recoveries 1,277 6,999 — — — 8,276 Net charge-offs (recoveries) 72,083 126,523 — 180 — 198,786 Ending balance $ 73,061 $ 84,064 $ 4,699 $ 92,791 $ — $ 254,615 Year ended December 31, 2019 Beginning balance $ 96,814 $ 34,882 $ — $ 52,595 $ 7,231 $ 191,522 Provision for credit losses on loans 46,738 57,680 2,265 (21,658) (7,231) 77,794 Charge-offs 44,352 32,625 — 662 — 77,639 Recoveries 3,054 316 — — — 3,370 Net charge-offs (recoveries) 41,298 32,309 — 662 — 74,269 Ending balance $ 102,254 $ 60,253 $ 2,265 $ 30,275 $ — $ 195,047
Schedule of impaired loans, by portfolio class	The following table summarizes collateral-dependent gross loans held for investment by collateral type as follows: Collateral Type (in thousands) Business Assets Real Property Oil/Gas Mineral Reserves Rolling Stock Total December 31, 2020 Commercial $ 3,361 $ — $ — $ 774 $ 4,135 Energy — — 5,156 — 5,156 Real estate CRE — 4,619 — — 4,619 Other — 11,372 — — 11,372 Total collateral-dependent loans held for investment $ 3,361 $ 15,991 $ 5,156 $ 774 $ 25,282
Schedule of an age analysis of accruing past due loans	The table below provides an age analysis of our loans held for investment: (in thousands) 30-59 Days 60-89 Days 90 Days or More Past Due(1) Total Past Non-accrual(2) Current Total Non-accrual With No Allowance December 31, 2020 Commercial $ 6,171 $ 2,602 $ 9,325 $ 18,098 $ 32,096 $ 8,811,386 $ 8,861,580 $ 6,917 Energy — — — — 51,724 714,493 766,217 17,759 Mortgage finance loans — — — — — 9,079,409 9,079,409 — Real estate CRE 2,926 297 — 3,223 10,601 3,672,596 3,686,420 5,749 RBF — — — — — 857,899 857,899 — Other 3,471 493 — 3,964 27,350 883,429 914,743 13,263 Secured by 1-4 family 1,340 1,467 3,216 6,023 218 329,321 335,562 — Total loans held for investment $ 13,908 $ 4,859 $ 12,541 $ 31,308 $ 121,989 $ 24,348,533 $ 24,501,830 $ 43,688 (1) Loans past due 90 days and still accruing includes premium finance loans of $6.4 million. These loans are generally secured by obligations of insurance carriers to refund premiums on canceled insurance policies. The receipt of the refund of premiums from the insurance carriers can take 180 days or longer from the cancellation date. (2) As of December 31, 2020 and December 31, 2019, none of our non-accrual loans were earning interest income on a cash basis. Additionally, no interest income was recognized on non-accrual loans for the year ended December 31, 2020. Accrued interest of $1.3 million was reversed during the year ended December 31, 2020.
Schedule of loans that have been restructured	The following table details the recorded investment at December 31, 2020 and 2019 of loans that have been restructured during the years ended December 31, 2020 and 2019 by type of modification: Extended Maturity Adjusted Payment Schedule Total (in thousands, except number of contracts) Number of Contracts Balance at Period End Number of Contracts Balance at Period End Number of Contracts Balance at Period End Year Ended December 31, 2020 Commercial 2 $ 7,390 2 $ 14,496 4 $ 21,886 Energy loans 1 5,705 3 12,935 4 18,640 Total 3 $ 13,095 5 $ 27,431 $ 8 $ 40,526 Year Ended December 31, 2019 Commercial 1 $ 1,753 3 $ 21,193 $ 4 $ 22,946 Energy loans 1 3,935 — — 1 3,935 Total 2 $ 5,688 3 $ 21,193 $ 5 $ 26,881

Certain Transfers of Financia_2

Certain Transfers of Financial Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Transfers and Servicing [Abstract]
Schedule of Loans Held-for-sale [Table Text Block]	The table below presents a reconciliation of the changes in loans held for sale: Year Ended December 31, (in thousands) 2020 2019 Outstanding balance(1): Beginning balance $ 2,568,362 $ 1,949,785 Loans purchased and originated 11,366,986 10,183,057 Payments and loans sold (13,654,211) (9,564,480) Ending balance 281,137 2,568,362 Fair value adjustment: Beginning balance 8,772 19,689 Increase/(decrease) to fair value (6,744) (10,917) Ending balance 2,028 8,772 Loans held for sale at fair value $ 283,165 $ 2,577,134
Schedule of Mortgage Servicing Rights Activity [Table Text Block]	retain the right to service the loans sold through our MCA program, creating MSRs which are recorded as assets on our balance sheet. A summary of MSR activity is as follows: Year Ended December 31, (in thousands) 2020 2019 MSRs: Balance, beginning of year $ 70,707 $ 42,474 Capitalized servicing rights 99,678 39,774 Amortization (38,994) (11,541) Sales — — Balance, end of period $ 131,391 $ 70,707 Valuation allowance: Balance, beginning of year $ 5,803 $ — Increase (decrease) in valuation allowance 20,164 5,803 Balance, end of period $ 25,967 $ 5,803 MSRs, net $ 105,424 $ 64,904 MSRs, fair value $ 105,424 $ 64,904
Schedule of Fair Value Assumption Used to Value Mortgage Servicing Rights Retained [Table Text Block]	The following summarizes the assumptions used by management to determine the fair value of MSRs: December 31, 2020 2019 Average discount rates 9.09 % 9.06 % Expected prepayment speeds 16.37 % 13.11 % Weighted-average life, in years 4.9 5.8
Schedule of Sensitivity Analysis of Fair Value, Transferor's Interests in Transferred Financial Assets [Table Text Block]	A sensitivity analysis of changes in the fair value of our MSR portfolio resulting from certain key assumptions is presented in the following table: December 31, (in thousands) 2020 2019 50 bp adverse change in prepayment speed $ (12,203) $ (10,768) 100 bp adverse change in prepayment speed (16,062) (17,965)

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Summary of lease cost and other information, operating leases	The table below summarizes our net lease cost: Year Ended December 31, (in thousands) 2020 2019 Operating lease cost $ 15,544 $ 14,844 Short-term lease cost 19 19 Variable lease cost 4,476 3,918 Sublease income (107) (126) Net lease cost $ 19,932 $ 18,655 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flows from operating leases $ 16,568 $ 14,711 Non-cash changes in ROU assets $ 765 $ 98,369 Non-cash changes in lease liabilities(1) $ 784 $ 108,189 (1) Includes $833,000 and $87.9 million in lease liabilities from new ROU assets obtained during the years ended December 31, 2020 and December 31, 2019, respectively. The table below summarizes other information related to our operating leases: December 31, 2020 2019 Weighted-average remaining lease term - operating leases, in years 6.5 7.2 Weighted-average discount rate - operating leases 2.74 % 2.75 %
Summary of maturity of remaining lease liabilities	The table below summarizes the maturity of remaining lease liabilities: (in thousands) December 31, 2020 2021 $ 17,222 2022 16,455 2023 16,511 2024 11,754 2025 5,524 2026 and thereafter 22,849 Total lease payments 90,315 Less: Interest (7,786) Present value of lease liabilities $ 82,529

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of goodwill and other intangible assets	Goodwill and other intangible assets are summarized as follows: (in thousands) Gross Goodwill and Intangible Assets Accumulated Net Goodwill and Intangible Assets December 31, 2020 Goodwill $ 15,468 $ (374) $ 15,094 Intangible assets—customer relationships and trademarks 9,006 (6,433) 2,573 Total goodwill and intangible assets $ 24,474 $ (6,807) $ 17,667 December 31, 2019 Goodwill $ 15,468 $ (374) $ 15,094 Intangible assets—customer relationships and trademarks 9,006 (6,001) 3,005 Total goodwill and intangible assets $ 24,474 $ (6,375) $ 18,099
Schedule of estimated aggregate future amortization expense for intangible assets	The estimated aggregate future amortization expense for intangible assets remaining as of December 31, 2020 is as follows: (in thousands) 2021 $ 405 2022 405 2023 382 2024 268 2025 268 Thereafter 845 Total $ 2,573

Premises and Equipment (Tables)

Premises and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Summary of premises and equipment	Premises and equipment are summarized as follows: December 31, (in thousands) 2020 2019 Premises $ 32,231 $ 30,181 Furniture and equipment 41,627 42,176 Total cost 73,858 72,357 Accumulated depreciation (49,312) (41,145) Total premises and equipment, net $ 24,546 $ 31,212

Deposits (Tables)

Deposits (Tables)	12 Months Ended
	Dec. 31, 2020
Deposits [Abstract]
Schedule of deposits	Deposits are summarized as follows: December 31, (in thousands) 2020 2019 Non-interest-bearing demand deposits $ 12,740,947 $ 9,438,459 Interest-bearing deposits: Transaction 4,396,243 3,651,128 Savings 11,619,880 10,517,975 Time 2,239,519 2,871,031 Total interest-bearing deposits 18,255,642 17,040,134 Total deposits $ 30,996,589 $ 26,478,593
Schedule of maturities of interest-bearing time deposits	The scheduled maturities of interest-bearing time deposits were as follows at December 31, 2020: (in thousands) 2021 $ 1,317,558 2022 795,656 2023 121,376 2024 1,921 2025 3,003 2026 and after 5 Total $ 2,239,519

Short-Term and Other Borrowin_2

Short-Term and Other Borrowings (Tables)	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
Summary of borrowings	The following table summarizes our short-term and other borrowings: (dollar amounts in thousands) Federal Funds Purchased Customer Repurchase Agreements FHLB Borrowings December 31, 2020 Amount outstanding at year-end $ 107,600 $ 4,151 $ 3,000,000 Interest rate at year-end 0.15 % 0.35 % 0.46 % Average balance outstanding during the year $ 207,121 $ 5,563 $ 2,902,732 Weighted-average interest rate during the year 0.52 % 0.47 % 0.72 % Maximum month-end outstanding during the year $ 300,430 $ 8,314 $ 4,900,000 December 31, 2019 Amount outstanding at year-end $ 132,270 $ 9,496 $ 2,400,000 Interest rate at year-end 1.66 % 0.61 % 1.68 % Average balance outstanding during the year $ 502,604 $ 11,655 $ 2,523,836 Weighted-average interest rate during the year 2.36 % 0.51 % 2.31 % Maximum month-end outstanding during the year $ 905,473 $ 14,208 $ 5,000,000 December 31, 2018 Amount outstanding at year-end $ 629,169 $ 12,005 $ 3,900,000 Interest rate at year-end 2.54 % 0.09 % 2.56 % Average balance outstanding during the year $ 323,140 $ 9,812 $ 1,769,452 Weighted-average interest rate during the year 2.02 % 0.09 % 2.05 % Maximum month-end outstanding during the year $ 629,169 $ 13,835 $ 4,000,000
Summary of other borrowing capacities	The following table summarizes our other borrowing capacities net of balances outstanding. As of December 31, 2020, all are scheduled to mature within one year. December 31, (in thousands) 2020 2019 2018 FHLB borrowing capacity relating to loans $ 7,653,317 $ 8,964,019 $ 4,568,842 FHLB borrowing capacity relating to securities 2,946,539 589 721 Total FHLB borrowing capacity(1) $ 10,599,856 $ 8,964,608 $ 4,569,563 Unused federal funds lines available from commercial banks $ 1,030,000 $ 1,432,000 $ 620,000 Unused Federal Reserve borrowings capacity $ 2,179,000 $ 3,637,238 $ 4,933,965 Unused revolving line of credit(2) $ 130,000 $ 130,000 $ 130,000 (1) FHLB borrowings are collateralized by a blanket floating lien on certain real estate secured loans, mortgage finance assets and also certain pledged securities. (2) Unsecured revolving, non-amortizing line of credit with maturity date of December 14, 2021. Proceeds may be used for general corporate purposes, including funding regulatory capital infusions into the Bank. The loan agreement contains customary financial covenants and restrictions. No borrowings were made against this line of credit during 2020, 2019, or 2018.

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2020
Subordinated Borrowings [Abstract]
Schedule of details of the trust preferred subordinated debentures	As of December 31, 2020, the details of the trust preferred subordinated debentures are summarized below: (dollar amounts in thousands) Texas Capital Texas Capital Texas Capital Texas Capital Texas Capital Date issued November 19, 2002 April 10, 2003 October 6, 2005 April 28, 2006 September 29, 2006 Trust preferred securities issued $10,310 $10,310 $25,774 $25,774 $41,238 Floating or fixed rate securities Floating Floating Floating Floating Floating Interest rate on subordinated debentures 3 month LIBOR + 3.35% 3 month LIBOR + 3.25% 3 month LIBOR + 1.51% 3 month LIBOR + 1.60% 3 month LIBOR + 1.71% Maturity date November 2032 April 2033 December 2035 June 2036 December 2036

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Schedule of income tax expense/(benefit)	Year ended December 31, (in thousands) 2020 2019 2018 Current: Federal $ 32,701 $ 69,427 $ 82,556 State 920 4,072 3,808 Total 33,621 73,499 86,364 Deferred: Federal (7,964) 10,796 (6,400) State — — — Total (7,964) 10,796 (6,400) Total expense: Federal 24,737 80,223 76,156 State 920 4,072 3,808 Total $ 25,657 $ 84,295 $ 79,964
Schedule of deferred tax assets and liabilities	December 31, (in thousands) 2020 2019 Deferred tax assets: Allowance for credit losses $ 59,279 $ 44,383 Operating lease liabilities 17,983 20,894 Loan origination fees 11,181 10,638 Stock compensation 3,913 3,605 Non-accrual interest 1,245 2,351 Non-qualified deferred compensation 5,795 4,027 Other 3,136 2,544 Total deferred tax assets 102,532 88,442 Deferred tax liabilities: Loan origination costs (2,997) (2,686) Leases (8,603) (7,912) Operating lease ROU assets (16,617) (19,644) MSRs (22,566) (13,818) Depreciation (14,968) (17,602) Unrealized gain on securities (4,193) (2,379) Other (3,381) (3,337) Total deferred tax liabilities (73,325) (67,378) Net deferred tax asset $ 29,207 $ 21,064
Reconciliation of income attributable to continuing operations	The reconciliation of income tax at the U.S. federal statutory tax rate to our income tax expense and effective tax rate is as follows: Year ended December 31, 2020 2019 2018 Amount Rate Amount Rate Amount Rate U.S. statutory rate $ 19,309 21 % $ 85,504 21 % $ 79,965 21 % State taxes 726 1 % 3,217 1 % 3,008 1 % Tax-exempt income (3,356) (4) % (5,127) (1) % (4,855) (1) % Tax credits (1,216) (1) % (2,052) (1) % (2,421) (1) % Disallowed FDIC 3,920 4 % 2,468 1 % 2,418 1 % Disallowed compensation 3,098 3 % 628 — % 400 — % Other 3,176 4 % (343) — % 1,449 — % Effective tax rate $ 25,657 28 % $ 84,295 21 % $ 79,964 21 %

Financial Instruments with Of_2

Financial Instruments with Off-Balance Sheet Risk (Tables)	12 Months Ended
	Dec. 31, 2020
Risks and Uncertainties [Abstract]
Schedule of financial instruments with off-balance sheet risk	The table below presents our financial instruments with off-balance sheet risk, as well as the activity in the allowance for off-balance sheet credit losses related to those financial instruments. This allowance is recorded in other liabilities on the consolidated balance sheet. Year Ended December 31, (in thousands) 2020 2019 Beginning balance of allowance for off-balance sheet credit losses $ 8,640 $ 11,434 Impact of CECL adoption 563 — Provision for off-balance sheet credit losses 8,231 (2,794) Ending balance of allowance for off-balance sheet credit losses $ 17,434 $ 8,640 Commitments to extend credit - period end balance $ 8,530,453 $ 8,066,655 Standby letters of credit - period end balance $ 268,894 $ 261,405

Regulatory Restrictions (Tables

Regulatory Restrictions (Tables)	12 Months Ended
	Dec. 31, 2020
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Schedule of compliance with Regulatory Capital Requirements	The table below summarizes our actual and required capital ratios under the Basel III Capital Rules: Actual Minimum capital Required - Basel III Fully Phased-In Required to be Considered Well Capitalized (dollars in thousands) Capital Amount Ratio Capital Amount Ratio Capital Amount Ratio December 31, 2020 CET1 Company $ 2,708,150 9.35 % $ 2,026,400 7.00 % N/A N/A Bank 2,744,211 9.48 % 2,025,417 7.00 % 1,880,745 6.50 % Total capital (to risk-weighted assets) Company 3,498,737 12.09 % 3,039,600 10.50 % N/A N/A Bank 3,375,983 11.67 % 3,038,126 10.50 % 2,893,453 10.00 % Tier 1 capital (to risk-weighted assets) Company 2,968,150 10.25 % 2,460,628 8.50 % N/A N/A Bank 2,904,211 10.04 % 2,459,435 8.50 % 2,314,763 8.00 % Tier 1 capital (to average assets)(1) Company 2,968,150 7.52 % 1,578,651 4.00 % N/A N/A Bank 2,904,211 7.36 % 1,578,207 4.00 % 1,972,758 5.00 % December 31, 2019 CET1 Company $ 2,653,999 8.88 % $ 2,091,591 7.00 % N/A N/A Bank 2,676,513 8.96 % 2,090,870 7.00 % 1,941,522 6.50 % Total capital (to risk-weighted assets) Company 3,398,345 11.37 % 3,137,926 10.50 % N/A N/A Bank 3,262,144 10.92 % 3,136,305 10.50 % 2,986,957 10.00 % Tier 1 capital (to risk-weighted assets) Company 2,912,529 9.75 % 2,540,226 8.50 % N/A N/A Bank 2,835,043 9.49 % 2,538,913 8.50 % 2,389,565 8.00 % Tier 1 capital (to average assets)(1) Company 2,912,529 8.42 % 1,383,640 4.00 % N/A N/A Bank 2,835,043 8.20 % 1,383,190 4.00 % 1,728,988 5.00 % (1) The Tier 1 capital ratio (to average assets) is not impacted by the Basel III Capital Rules; however, the Federal Reserve and the FDIC may require the Company and the Bank, respectively, to maintain a Tier 1 capital ratio (to average assets) above the required minimum.

Stock-Based Compensation and _2

Stock-Based Compensation and Employee Benefits (Tables)	12 Months Ended
	Dec. 31, 2020
Compensation Related Costs [Abstract]
Schedule of stock appreciation rights activity	A summary of our SAR activity and related information is as follows. Grants of SARs include time-based vesting conditions that generally vest ratably over a period of five years. December 31, 2020 December 31, 2019 December 31, 2018 SARs Weighted Average Exercise Price SARs Weighted Average Exercise Price SARs Weighted Average Exercise Price SARs outstanding at beginning of year 21,200 $ 33.95 41,350 $ 29.13 74,363 $ 30.12 SARs exercised (8,800) 20.52 (20,150) 24.07 (33,013) 31.35 SARs outstanding at year-end 12,400 $ 43.48 21,200 $ 33.95 41,350 $ 29.13 SARs vested and exercisable at year-end 12,400 $ 43.48 21,200 $ 33.95 39,750 $ 27.81 Weighted average remaining contractual life of SARs vested (in years) 2.26 2.14 2.33 Weighted average remaining contractual life of SARs outstanding (in years) 2.26 2.14 2.44 Compensation expense $ — $ 6,000 $ 121,000 Unrecognized compensation expense $ — $ — $ 6,000 Weighted average period over which unrecognized compensation expense is expected to be recognized (in years) 0.00 0.00 0.17 Fair value of shares vested during the year $ — $ 37,000 $ 211,000 Intrinsic value of SARs exercised $ 294,000 $ 724,000 $ 1,919,000
Summary of status and changes in nonvested restricted stock units	A summary of our RSU activity and related information is as follows. Grants of RSUs include time-based vesting conditions that generally vest ratably over a period of three three four December 31, 2020 December 31, 2019 December 31, 2018 RSUs Weighted RSUs Weighted RSUs Weighted RSUs outstanding at beginning of year 558,312 $ 64.95 349,533 $ 69.11 423,732 $ 60.01 RSUs granted 631,092 39.37 386,913 59.28 95,891 88.07 RSUs vested (171,494) 65.17 (140,666) 59.97 (121,507) 54.97 RSUs forfeited (62,316) 56.92 (37,468) 62.73 (48,583) 63.60 RSUs outstanding at year-end 955,594 $ 48.76 558,312 $ 64.95 349,533 $ 69.11 Compensation expense $ 15,655,000 $ 11,733,000 $ 8,803,000 Unrecognized compensation expense $ 29,146,000 $ 25,305,000 $ 16,538,000 Weighted average period over which unrecognized compensation expense is expected to be recognized (in years) 2.83 3.09 2.90

Fair Value Disclosures (Tables)

Fair Value Disclosures (Tables)	12 Months Ended
	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of assets and liabilities measured at fair value	Assets and liabilities measured at fair value are as follows: Fair Value Measurements Using (in thousands) Level 1 Level 2 Level 3 December 31, 2020 Available-for-sale debt securities:(1) U.S. government agency securities $ — $ 123,589 $ — Residential mortgage-backed securities — 2,828,956 — Tax-exempt asset-backed securities — — 199,176 CRT Securities — — 11,417 Equity securities(1)(2) 26,593 7,239 — Loans held for sale(3) — 232,147 6,933 Loans held for investment(4) — — 21,209 Derivative assets(5) — 102,720 — Derivative liabilities(5) — 99,255 — Non-qualified deferred compensation plan liabilities(6) 26,593 — — December 31, 2019 Available-for-sale debt securities:(1) Residential mortgage-backed securities $ — $ 5,266 $ — Tax-exempt asset-backed securities — — 197,027 CRT Securities — — 11,964 Equity securities(1)(2) 18,484 7,130 — Loans held for sale(3) — 2,564,281 7,043 Loans held for investment(4) — — 109,585 Derivative assets(5) — 48,684 — Derivative liabilities(5) — 51,310 — Non-qualified deferred compensation plan liabilities(6) 18,484 — — (1) Securities are measured at fair value on a recurring basis, generally monthly, except for tax-exempt asset-backed securities and CRT securities which are measured quarterly. (2) Equity securities consist of Community Reinvestment Act funds and investments related to our non-qualified deferred compensation plan. (3) Loans held for sale purchased through our MCA program are measured at fair value on a recurring basis, generally monthly. (4) Includes certain collateral-dependent loans held for investment for which a specific allocation of the allowance for credit losses is based upon the fair value of the loan’s underlying collateral. These loans held for investment are measured on a nonrecurring basis, generally annually or more often as warranted by market and economic conditions. (5) Derivative assets and liabilities are measured at fair value on a recurring basis, generally quarterly. (6) Non-qualified deferred compensation plan liabilities represent the fair value of the obligation to the employee, which generally corresponds to the fair value of the invested assets, and are measured at fair value on a recurring basis, generally monthly.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation	The following table presents a reconciliation of the level 3 fair value category measured at fair value on a recurring basis: Net Realized/Unrealized Gains (Losses) (in thousands) Balance at Beginning of Period Purchases / Additions Sales / Reductions Realized Unrealized Balance at End of Period Year ended December 31, 2020 Available-for-sale debt securities:(1) Tax-exempt asset-backed securities $ 197,027 $ 8,470 $ (6,755) $ — $ 434 $ 199,176 CRT Securities $ 11,964 $ — $ — $ — $ (547) $ 11,417 Loans held for sale(2) $ 7,043 $ 1,472 $ (2,077) $ 248 $ 247 $ 6,933 Year ended December 31, 2019 Available-for-sale debt securities:(1) Tax-exempt asset-backed securities $ 95,804 $ 92,010 $ (4,302) $ — $ 13,515 $ 197,027 CRT Securities $ — $ 15,044 $ — $ (331) $ (2,749) $ 11,964 Loans held for sale(2) $ 16,415 $ 321 $ (10,690) $ 190 $ 807 $ 7,043 (1) Unrealized gains/(losses) on available-for-sale debt securities are recorded in AOCI and relate to assets that remain outstanding at period end. Realized gains/(losses) are recorded in other non-interest income. (2) Realized and unrealized gains/(losses) on loans held for sale are recorded in gain/(loss) on sale of loans held for sale.
Summary of the carrying amounts and estimated fair values of financial instruments	A summary of the carrying amounts and estimated fair values of financial instruments is as follows: December 31, 2020 December 31, 2019 (in thousands) Carrying Estimated Carrying Estimated Financial assets: Level 1 inputs: Cash and cash equivalents $ 9,206,380 $ 9,206,380 $ 4,425,583 $ 4,425,583 Investment securities 26,593 26,593 18,484 18,484 Level 2 inputs: Investment securities 2,959,784 2,959,784 12,396 12,396 Loans held for sale 232,147 232,147 2,570,091 2,570,091 Derivative assets 102,720 102,720 48,684 48,684 Level 3 inputs: Investment securities 210,593 210,593 208,991 208,991 Loans held for sale 6,933 6,933 7,043 7,043 Loans held for investment, net 24,176,245 24,233,185 24,451,215 24,478,586 Financial liabilities: Level 2 inputs: Federal funds purchased 107,600 107,600 132,270 132,270 Customer repurchase agreements 4,151 4,151 9,496 9,496 Other borrowings 3,000,000 3,000,000 2,400,000 2,400,000 Subordinated notes 282,490 291,704 282,129 292,302 Trust preferred subordinated debentures 113,406 113,406 113,406 113,406 Derivative liabilities 99,255 99,255 51,310 51,310 Level 3 inputs: Deposits 30,996,589 30,997,980 26,478,593 26,486,090

Parent Company Only (Tables)

Parent Company Only (Tables)	12 Months Ended
	Dec. 31, 2020
Condensed Financial Information Disclosure [Abstract]
Balance Sheet	Balance Sheet December 31, (in thousands) 2020 2019 Assets Cash and cash equivalents $ 57,472 $ 71,462 Loans held for investment (net of unearned income) 7,500 10,500 Investment in subsidiaries 2,930,843 2,847,393 Other assets 89,551 88,639 Total assets $ 3,085,366 $ 3,017,994 Liabilities and Stockholders’ Equity Other liabilities $ 1,320 $ 1,768 Subordinated notes 108,816 108,715 Trust preferred subordinated debentures 113,406 113,406 Total liabilities 223,542 223,889 Preferred stock 150,000 150,000 Common stock 504 503 Additional paid-in capital 1,002,050 988,357 Retained earnings 1,693,504 1,646,303 Treasury stock (8) (8) Accumulated other comprehensive income 15,774 8,950 Total stockholders’ equity 2,861,824 2,794,105 Total liabilities and stockholders’ equity $ 3,085,366 $ 3,017,994
Statement of Earnings	Statement of Income Year ended December 31, (in thousands) 2020 2019 2018 Interest on loans $ 3,402 $ 3,401 $ 3,398 Dividend income 10,400 10,400 10,400 Other income 96 151 142 Total income 13,898 13,952 13,940 Other non-interest income 3 17 7 Interest expense 10,515 12,342 12,031 Salaries and employee benefits 725 607 588 Legal and professional 3,238 3,093 2,020 Other non-interest expense 4,553 1,889 2,013 Total expense 19,031 17,931 16,652 Income (loss) before income taxes and equity in undistributed income of subsidiary (5,130) (3,962) (2,705) Income tax expense (benefit) (1,135) (861) (587) Income (loss) before equity in undistributed income of subsidiary (3,995) (3,101) (2,118) Equity in undistributed income of subsidiary 68,100 312,932 293,321 Net income 64,105 309,831 291,203 Preferred stock dividends 9,750 9,750 9,750 Net income available to common stockholders $ 54,355 $ 300,081 $ 281,453
Statement of Cash Flows	Statements of Cash Flows Year ended December 31, (in thousands) 2020 2019 2018 Operating Activities Net income $ 64,105 $ 309,831 $ 291,203 Adjustments to reconcile net income to net cash used in operating activities: Equity in undistributed income of subsidiary (68,100) (312,932) (293,321) Amortization 101 101 101 Increase in other assets (912) (1,187) (1,152) Increase (decrease) in other liabilities (448) 297 227 Net cash used in operating activities (5,254) (3,890) (2,942) Investing Activities Net (increase)/decrease in loans held for investment 3,000 (3,000) — Investments in and advances to subsidiaries — — (40,000) Net cash provided by/(used in) investing activities 3,000 (3,000) (40,000) Financing Activities Proceeds from sale of stock related to stock-based awards (1,986) (1,459) (2,382) Preferred dividends paid (9,750) (9,750) (9,750) Net cash used in financing activities (11,736) (11,209) (12,132) Net decrease in cash and cash equivalents (13,990) (18,099) (55,074) Cash and cash equivalents at beginning of year 71,462 89,561 144,635 Cash and cash equivalents at end of year $ 57,472 $ 71,462 $ 89,561

Derivative Financial Instrume_2

Derivative Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The notional amounts and estimated fair values of derivative positions outstanding are presented in the following table: December 31, 2020 December 31, 2019 Estimated Fair Value Estimated Fair Value (in thousands) Notional Asset Derivative Liability Derivative Notional Asset Derivative Liability Derivative Non-hedging derivatives: Financial institution counterparties: Commercial loan/lease interest rate swaps $ 1,922,956 $ 71 $ 96,246 $ 1,548,234 $ 182 $ 46,518 Commercial loan/lease interest rate caps 565,634 34 — 639,163 32 — Foreign currency forward contracts 6,667 214 78 2,219 169 — Customer counterparties: Commercial loan/lease interest rate swaps 1,922,956 96,246 71 1,548,234 46,518 182 Commercial loan/lease interest rate caps 565,634 — 34 639,163 — 32 Foreign currency forward contracts 6,667 78 214 2,219 — 169 Economic hedging derivatives to hedge: Residential MSRs: Interest rate swap futures 320,000 474 — — — — Forward sale commitments 155,000 551 — — — — Loans held for sale: Loan purchase commitments 332,145 5,123 8 214,012 1,965 4 Forward sale commitments 485,326 — 2,675 2,654,653 — 4,587 Gross derivatives 102,791 99,326 48,866 51,492 Offsetting derivative assets/liabilities (71) (71) (182) (182) Net derivatives included in the consolidated balance sheets $ 102,720 $ 99,255 $ 48,684 $ 51,310
Schedule Of Weighted Average Interest Rate Received And Paid	The weighted-average received and paid interest rates for interest rate swaps outstanding were as follows: December 31, 2020 December 31, 2019 Received Paid Received Paid Non-hedging interest rate swaps 3.14 % 1.38 % 3.94 % 3.26 %

Quarterly Financial Data (Table

Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2020
Selected Quarterly Financial Information [Abstract]
Schedule of Quarterly Financial Information	2020 Selected Quarterly Financial Data (in thousands, except per share data) Fourth Third Second First Interest income $ 255,163 $ 243,731 $ 252,010 $ 306,008 Interest expense 32,153 36,162 42,082 77,689 Net interest income 223,010 207,569 209,928 228,319 Provision for credit losses 32,000 30,000 100,000 96,000 Net interest income after provision for credit losses 191,010 177,569 109,928 132,319 Non-interest income 42,886 60,348 70,502 11,780 Non-interest expense 150,886 165,741 222,352 165,417 Income/(loss) before income taxes 83,010 72,176 (41,922) (21,318) Income tax expense/(benefit) 22,834 15,060 (7,606) (4,631) Net income/(loss) 60,176 57,116 (34,316) (16,687) Preferred stock dividends 2,437 2,438 2,437 2,438 Net income/(loss) available to common stockholders $ 57,739 $ 54,678 $ (36,753) $ (19,125) Basic earnings/(loss) per share: $ 1.14 $ 1.08 $ (0.73) $ (0.38) Diluted earnings/(loss) per share: $ 1.14 $ 1.08 $ (0.73) $ (0.38) 2019 Selected Quarterly Financial Data (in thousands, except per share data) Fourth Third Second First Interest income $ 337,757 $ 355,101 $ 346,893 $ 325,561 Interest expense 89,372 102,933 103,340 89,947 Net interest income 248,385 252,168 243,553 235,614 Provision for credit losses 17,000 11,000 27,000 20,000 Net interest income after provision for credit losses 231,385 241,168 216,553 215,614 Non-interest income 17,761 20,301 24,364 30,014 Non-interest expense 168,187 149,429 141,718 141,516 Income before income taxes 80,959 112,040 99,199 104,112 Income tax expense 16,539 23,958 21,387 22,411 Net income 64,420 88,082 77,812 81,701 Preferred stock dividends 2,437 2,438 2,437 2,438 Net income available to common stockholders $ 61,983 $ 85,644 $ 75,375 $ 79,263 Basic earnings per share: $ 1.23 $ 1.70 $ 1.50 $ 1.58 Diluted earnings per share: $ 1.23 $ 1.70 $ 1.50 $ 1.58

Operations and Summary of Sig_4

Operations and Summary of Significant Accounting Policies - Revision of Prior Period Financial Statements, Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other liabilities	$ 339,486		$ 318,094	$ 214,324	$ 194,861
Total liabilities	34,854,872		29,746,748	25,777,459	22,885,573
Retained earnings	1,713,056	$ 1,663,671	1,663,671	1,361,406	1,077,851	$ 891,520
Total stockholders’ equity	$ 2,871,224		2,801,321	2,480,308	2,190,072	1,997,890
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other liabilities			287,157	194,238	182,212
Total liabilities			29,715,811	25,757,373	22,872,924
Retained earnings			1,694,608	1,381,492	1,090,500	903,187
Total stockholders’ equity			2,832,258	2,500,394	2,202,721	2,009,557
Revision of Prior Period, Error Correction, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Other liabilities			30,937	20,086	12,649
Total liabilities			30,937	20,086	12,649
Retained earnings			(30,937)	(20,086)	(12,649)	(11,667)
Total stockholders’ equity			$ (30,937)	$ (20,086)	$ (12,649)	$ (11,667)

Operations and Summary of Sig_5

Operations and Summary of Significant Accounting Policies - Revision of Prior Period Financial Statements, Income Statement (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Salaries and employee benefits									$ 340,529	$ 328,483	$ 300,899	$ 266,461
Other non-interest expense									41,809	44,701	49,670	48,048
Non-interest expense	$ 150,886	$ 165,741	$ 222,352	$ 165,417	$ 168,187	$ 149,429	$ 141,718	$ 141,516	704,396	600,850	532,533	466,858
Income/(loss) before income taxes	83,010	72,176	(41,922)	(21,318)	80,959	112,040	99,199	104,112	91,946	396,310	373,351	324,726
Net income/(loss)	60,176	57,116	(34,316)	(16,687)	64,420	88,082	77,812	81,701	66,289	312,015	293,387	196,081
Net income/(loss) available to common stockholders	$ 57,739	$ 54,678	$ (36,753)	$ (19,125)	$ 61,983	$ 85,644	$ 75,375	$ 79,263	56,539	302,265	283,637	186,331
Comprehensive income									$ 73,113	320,447	293,393	196,094
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Salaries and employee benefits										315,080	291,768	264,231
Other non-interest expense										47,253	51,364	49,296
Non-interest expense										589,999	525,096	465,876
Income/(loss) before income taxes										407,161	380,788	325,708
Net income/(loss)										322,866	300,824	197,063
Net income/(loss) available to common stockholders										313,116	291,074	187,313
Comprehensive income										331,298	300,830	197,076
Revision of Prior Period, Error Correction, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Salaries and employee benefits										13,403	9,131	2,230
Other non-interest expense										(2,552)	(1,694)	(1,248)
Non-interest expense										10,851	7,437	982
Income/(loss) before income taxes										(10,851)	(7,437)	(982)
Net income/(loss)										(10,851)	(7,437)	(982)
Net income/(loss) available to common stockholders										(10,851)	(7,437)	(982)
Comprehensive income										$ (10,851)	$ (7,437)	$ (982)

Operations and Summary of Sig_6

Operations and Summary of Significant Accounting Policies - Revision of Prior Period Financial Statements, Equity Statement (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance retained earnings	$ 1,663,671	$ 1,663,671	$ 1,361,406	$ 1,077,851	$ 891,520
Beginning balance		2,801,321	2,480,308	2,190,072	1,997,890
Ending balance retained earnings	1,713,056	1,663,671	1,663,671	1,361,406	1,077,851
Ending balance	$ 2,871,224		2,801,321	2,480,308	2,190,072
Previously Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance retained earnings		1,694,608	1,381,492	1,090,500	903,187
Beginning balance		2,832,258	2,500,394	2,202,721	2,009,557
Ending balance retained earnings			1,694,608	1,381,492	1,090,500
Ending balance			2,832,258	2,500,394	2,202,721
Revision of Prior Period, Error Correction, Adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Beginning balance retained earnings		(30,937)	(20,086)	(12,649)	(11,667)
Beginning balance		$ (30,937)	(20,086)	(12,649)	(11,667)
Ending balance retained earnings			(30,937)	(20,086)	(12,649)
Ending balance			$ (30,937)	$ (20,086)	$ (12,649)

Operations and Summary of Sig_7

Operations and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Redemption value	$ 7,800
ROU asset	67,000	$ 80,000
Lease liability	$ 82,529	$ 95,900
Cumulative Effect, Period of Adoption, Adjustment
Property, Plant and Equipment [Line Items]
ROU asset			$ 64,000
Lease liability			$ 74,000
Minimum
Property, Plant and Equipment [Line Items]
PPE, useful life	3 years
Finite-lived intangible asset, useful life	1 year
Term of lease contract	5 years
Maximum
Property, Plant and Equipment [Line Items]
PPE, useful life	5 years
Finite-lived intangible asset, useful life	5 years
Term of lease contract	10 years

Operations and Summary of Sig_8

Operations and Summary of Significant Accounting Policies - Impact of ASU 2016-13 (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets
Gross loans held for investment	$ 24,501,830			$ 24,736,642
Allowance for credit losses on loans	(254,615)		$ (195,047)	(195,047)	$ (191,522)
Loans held for investment, net	24,176,245		24,451,215	24,451,215
Net deferred tax asset	29,207		21,064	21,064
Liabilities:
Allowance for credit losses on off-balance sheet exposures	17,434		8,640	8,640	11,434
Equity:
Retained earnings	1,713,056		1,663,671	1,663,671	1,361,406	$ 1,077,851	$ 891,520
Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Allowance for credit losses on loans			(203,632)
Loans held for investment, net			24,442,630
Net deferred tax asset			23,058
Liabilities:
Allowance for credit losses on off-balance sheet exposures			9,203
Equity:
Retained earnings			1,656,517
Cumulative Effect, Period of Adoption, Adjustment
Assets
Allowance for credit losses on loans			(8,585)	(8,585)
Loans held for investment, net			(8,585)
Net deferred tax asset			1,994
Liabilities:
Allowance for credit losses on off-balance sheet exposures		$ 563	563	563
Equity:
Retained earnings			(7,154)
Commercial Portfolio Segment
Assets
Gross loans held for investment	8,861,580		10,230,828	9,133,444
Allowance for credit losses on loans	(73,061)			(102,254)	(96,814)
Commercial Portfolio Segment | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment			9,133,444
Commercial Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			(1,097,384)
Allowance for credit losses on loans				15,740
Energy Portfolio Segment
Assets
Gross loans held for investment	766,217			1,425,309
Allowance for credit losses on loans	(84,064)			(60,253)	(34,882)
Energy Portfolio Segment | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment			1,425,309
Energy Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			1,425,309
Allowance for credit losses on loans				(24,154)
Mortgage Finance Portfolio Segment
Assets
Gross loans held for investment	9,079,409		8,169,849	8,169,849
Allowance for credit losses on loans	(4,699)			(2,265)	0
Mortgage Finance Portfolio Segment | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment			8,169,849
Mortgage Finance Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			0
Allowance for credit losses on loans				(2,031)
Construction
Assets
Gross loans held for investment			2,563,339
Construction | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment
Construction | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			(2,563,339)
Real Estate Portfolio Segment
Assets
Gross loans held for investment	5,794,624		3,444,701	6,008,040
Allowance for credit losses on loans	$ (92,791)			(30,275)	$ (52,595)
Real Estate Portfolio Segment | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment			6,008,040
Real Estate Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			2,563,339
Allowance for credit losses on loans				$ 1,860
Consumer
Assets
Gross loans held for investment			71,463
Consumer | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment
Consumer | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			(71,463)
Equipment leases
Assets
Gross loans held for investment			256,462
Equipment leases | Cumulative Effect, Period Of Adoption, Adjusted Balance
Assets
Gross loans held for investment
Equipment leases | Cumulative Effect, Period of Adoption, Adjustment
Assets
Gross loans held for investment			$ (256,462)

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net income	$ 60,176	$ 57,116	$ (34,316)	$ (16,687)	$ 64,420	$ 88,082	$ 77,812	$ 81,701	$ 66,289	$ 312,015	$ 293,387	$ 196,081
Preferred stock dividends	2,437	2,438	2,437	2,438	2,437	2,438	2,437	2,438	9,750	9,750	9,750
Net income available to common stockholders	$ 57,739	$ 54,678	$ (36,753)	$ (19,125)	$ 61,983	$ 85,644	$ 75,375	$ 79,263	$ 56,539	$ 302,265	$ 283,637	$ 186,331
Denominator:
Denominator for basic earnings per share—weighted average shares									50,430,326	50,286,300	49,936,702
Effect of employee stock-based awards									152,653	132,904	218,275
Effect of warrants to purchase common stock									0	0	117,895
Denominator for dilutive earnings per share—adjusted weighted average shares and assumed conversions									50,582,979	50,419,204	50,272,872
Basic earnings per common share	$ 1.14	$ 1.08	$ (0.73)	$ (0.38)	$ 1.23	$ 1.70	$ 1.50	$ 1.58	$ 1.12	$ 6.01	$ 5.68
Diluted earnings per common share	$ 1.14	$ 1.08	$ (0.73)	$ (0.38)	$ 1.23	$ 1.70	$ 1.50	$ 1.58	$ 1.12	$ 5.99	$ 5.64
Stock options excluded from computation of EPS									453,024	86,308	27,100

Investment Securities (Details)

Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost(1)	$ 3,143,171	$ 202,929
Gross Unrealized Gains	25,803	14,077
Gross Unrealized Losses	(5,836)	(2,749)
Estimated Fair Value	3,163,138	214,257
Interest receivable	56,500	63,400
Available-for-sale Securities [Member]
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Interest receivable	6,000	1,600
U.S. government agency securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost(1)	125,000
Gross Unrealized Gains	1
Gross Unrealized Losses	(1,412)
Estimated Fair Value	123,589
Residential mortgage-backed securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost(1)	2,818,518	4,991
Gross Unrealized Gains	11,566	275
Gross Unrealized Losses	(1,128)	0
Estimated Fair Value	2,828,956	5,266
Tax-exempt asset-backed securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost(1)	184,940	183,225
Gross Unrealized Gains	14,236	13,802
Gross Unrealized Losses	0	0
Estimated Fair Value	199,176	197,027
CRT Securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost(1)	14,713	14,713
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(3,296)	(2,749)
Estimated Fair Value	$ 11,417	$ 11,964

Investment Securities (Details

Investment Securities (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amortized cost
Amortized Cost	$ 3,143,171	$ 202,929
Estimated fair value
Debt securities	3,163,138	214,257
Weighted average yield
Total	$ 3,163,138	$ 214,257
Available-for-sale Securities, Other Disclosure Items
Federal tax rate (percent)	21.00%	21.00%	21.00%
U.S. government agency securities
Amortized cost
Less Than One Year	$ 0
After One Through Five Years	0
After Five Through Ten Years	125,000
After Ten Years	0
Amortized Cost	125,000
Estimated fair value
Less Than One Year	0
After One Through Five Years	0
After Five Through Ten Years	123,589
After Ten Years	0
Debt securities	$ 123,589
Weighted average yield
Less Than One Year	0.00%
After One Through Five Years	0.00%
After Five Through Ten Years	1.13%
After Ten Years	0.00%
Total	1.13%
Residential mortgage-backed securities
Amortized cost
Less Than One Year	$ 0	$ 0
After One Through Five Years	545	1,005
After Five Through Ten Years	17,500	0
After Ten Years	2,800,473	3,986
Amortized Cost	2,818,518	4,991
Estimated fair value
Less Than One Year	0	0
After One Through Five Years	605	1,088
After Five Through Ten Years	17,490	0
After Ten Years	2,810,861	4,178
Debt securities	$ 2,828,956	$ 5,266
Weighted average yield
Less Than One Year	0.00%	0.00%
After One Through Five Years	4.58%	5.54%
After Five Through Ten Years	1.08%	0.00%
After Ten Years	1.25%	4.31%
Total	1.25%	4.55%
Tax-exempt asset-backed securities
Amortized cost
Less Than One Year	$ 0	$ 0
After One Through Five Years	0	0
After Five Through Ten Years	0	0
After Ten Years	184,940	183,225
Amortized Cost	184,940	183,225
Estimated fair value
Less Than One Year	0	0
After One Through Five Years	0	0
After Five Through Ten Years	0	0
After Ten Years	199,176	197,027
Debt securities	$ 199,176	$ 197,027
Weighted average yield
Less Than One Year	0.00%	0.00%
After One Through Five Years	0.00%	0.00%
After Five Through Ten Years	0.00%	0.00%
After Ten Years	4.92%	5.32%
Total	4.92%	5.32%
CRT Securities
Amortized cost
Less Than One Year	$ 0	$ 0
After One Through Five Years	0	0
After Five Through Ten Years	0	0
After Ten Years	14,713	14,713
Amortized Cost	14,713	14,713
Estimated fair value
Less Than One Year	0	0
After One Through Five Years	0	0
After Five Through Ten Years	0	0
After Ten Years	11,417	11,964
Debt securities	$ 11,417	$ 11,964
Weighted average yield
Less Than One Year	0.00%	0.00%
After One Through Five Years	0.00%	0.00%
After Five Through Ten Years	0.00%	0.00%
After Ten Years	0.15%	1.71%
Total	0.15%	1.71%

Investment Securities - Narrati

Investment Securities - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Estimated fair value	$ 33.8	$ 25.6
Customer Repurchase Agreements [Member]
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities pledged to secure certain customer repurchase agreements and deposits	31.7	3.5
Deposits
Debt Securities, Available-for-sale [Line Items]
Available-for-sale debt securities pledged to secure certain customer repurchase agreements and deposits	$ 1.9	$ 1.2

Investment Securities (Detail_2

Investment Securities (Details 2) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	$ 452,975	$ 11,964
Less Than 12 Months, Unrealized Loss	(2,540)	(2,749)
12 Months or Longer, Fair Value	11,417	0
12 Months or Longer, Unrealized Loss	(3,296)	0
Total, Fair Value	464,392	11,964
Total, Unrealized Loss	(5,836)	(2,749)
U.S. government agency securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	98,588
Less Than 12 Months, Unrealized Loss	(1,412)
12 Months or Longer, Fair Value	0
12 Months or Longer, Unrealized Loss	0
Total, Fair Value	98,588
Total, Unrealized Loss	(1,412)
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	354,387
Less Than 12 Months, Unrealized Loss	(1,128)
12 Months or Longer, Fair Value	0
12 Months or Longer, Unrealized Loss	0
Total, Fair Value	354,387
Total, Unrealized Loss	(1,128)
CRT Securities
Debt Securities, Available-for-sale [Line Items]
Less Than 12 Months, Fair Value	0	11,964
Less Than 12 Months, Unrealized Loss	0	(2,749)
12 Months or Longer, Fair Value	11,417	0
12 Months or Longer, Unrealized Loss	(3,296)	0
Total, Fair Value	11,417	11,964
Total, Unrealized Loss	$ (3,296)	$ (2,749)

Investment Securities (Detail_3

Investment Securities (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Net gains/(losses) recognized during the period	$ 2,998	$ 2,383
Less: Realized net gains/(losses) recognized during the period on equity securities sold	1,418	119
Unrealized net gains/(losses) recognized during the period on equity securities still held	$ 1,580	$ 2,264

Loans Held for Investment and_3

Loans Held for Investment and Allowance for Loan Losses - Loans Held for Investment by Portfolio Segment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans held for investment	$ 24,501,830		$ 24,736,642
Deferred income (net of direct origination costs)	(70,970)		(90,380)
Allowance for credit losses on loans	(254,615)	$ (195,047)	(195,047)	$ (191,522)
Loans held for investment, net	24,176,245	24,451,215	24,451,215
Mortgage obligations, amount	1,200,000		682,700
Interest receivable	56,500		63,400
Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans held for investment	8,861,580	10,230,828	9,133,444
Allowance for credit losses on loans	(73,061)		(102,254)	(96,814)
Energy Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans held for investment	766,217		1,425,309
Allowance for credit losses on loans	(84,064)		(60,253)	(34,882)
Mortgage Finance Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans held for investment	9,079,409	8,169,849	8,169,849
Allowance for credit losses on loans	(4,699)		(2,265)	0
Real Estate Portfolio Segment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross loans held for investment	5,794,624	$ 3,444,701	6,008,040
Allowance for credit losses on loans	$ (92,791)		$ (30,275)	$ (52,595)

Loans Held for Investment and_4

Loans Held for Investment and Allowance for Loan Losses - Loans by Investment Grade (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	$ 2,804,231
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	5,216,591
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,643,706
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,690,775
Financing Receivable, Originated Four Years before Latest Fiscal Year	747,648
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	6,831,441
Financing Receivable, Revolving	4,369,332
Financing Receivable, Revolving, Converted To Term Loans	198,106
Gross loans held for investment	24,501,830		$ 24,736,642
Commercial Portfolio Segment
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,280,206
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,955,654
Financing Receivable, Originated Two Years before Latest Fiscal Year	600,634
Financing Receivable, Originated Three Years before Latest Fiscal Year	434,411
Financing Receivable, Originated Four Years before Latest Fiscal Year	210,142
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	248,298
Financing Receivable, Revolving	3,067,092
Financing Receivable, Revolving, Converted To Term Loans	65,143
Gross loans held for investment	8,861,580	$ 10,230,828	9,133,444
Commercial Portfolio Segment | Pass
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,259,949
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	2,816,425
Financing Receivable, Originated Two Years before Latest Fiscal Year	543,438
Financing Receivable, Originated Three Years before Latest Fiscal Year	374,455
Financing Receivable, Originated Four Years before Latest Fiscal Year	192,060
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	213,212
Financing Receivable, Revolving	3,020,353
Financing Receivable, Revolving, Converted To Term Loans	40,253
Gross loans held for investment	8,460,145
Commercial Portfolio Segment | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	2,664
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	115,015
Financing Receivable, Originated Two Years before Latest Fiscal Year	38,751
Financing Receivable, Originated Three Years before Latest Fiscal Year	26,423
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,983
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	290
Financing Receivable, Revolving	19,971
Financing Receivable, Revolving, Converted To Term Loans	22,797
Gross loans held for investment	227,894
Commercial Portfolio Segment | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	15,773
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	15,854
Financing Receivable, Originated Two Years before Latest Fiscal Year	18,068
Financing Receivable, Originated Three Years before Latest Fiscal Year	32,241
Financing Receivable, Originated Four Years before Latest Fiscal Year	15,297
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	19,639
Financing Receivable, Revolving	22,932
Financing Receivable, Revolving, Converted To Term Loans	1,641
Gross loans held for investment	141,445
Commercial Portfolio Segment | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	1,820
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	8,360
Financing Receivable, Originated Two Years before Latest Fiscal Year	377
Financing Receivable, Originated Three Years before Latest Fiscal Year	1,292
Financing Receivable, Originated Four Years before Latest Fiscal Year	802
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	15,157
Financing Receivable, Revolving	3,836
Financing Receivable, Revolving, Converted To Term Loans	452
Gross loans held for investment	32,096
Energy Portfolio Segment
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	12,020
Financing Receivable, Originated Two Years before Latest Fiscal Year	7,598
Financing Receivable, Originated Three Years before Latest Fiscal Year	32,636
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,972
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	45,117
Financing Receivable, Revolving	666,874
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	766,217		1,425,309
Energy Portfolio Segment | Pass
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	12,020
Financing Receivable, Originated Two Years before Latest Fiscal Year	7,598
Financing Receivable, Originated Three Years before Latest Fiscal Year	26,931
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	23,750
Financing Receivable, Revolving	553,970
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	624,269
Energy Portfolio Segment | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	13,358
Financing Receivable, Revolving	76,866
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	90,224
Energy Portfolio Segment | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Energy Portfolio Segment | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	5,705
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,972
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	8,009
Financing Receivable, Revolving	36,038
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	51,724
Mortgage Finance Portfolio Segment
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	755,309
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,063,641
Financing Receivable, Originated Two Years before Latest Fiscal Year	821,122
Financing Receivable, Originated Three Years before Latest Fiscal Year	483,436
Financing Receivable, Originated Four Years before Latest Fiscal Year	106,013
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	5,849,888
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	9,079,409	8,169,849	8,169,849
Mortgage Finance Portfolio Segment | Pass
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	755,309
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,063,641
Financing Receivable, Originated Two Years before Latest Fiscal Year	821,122
Financing Receivable, Originated Three Years before Latest Fiscal Year	483,436
Financing Receivable, Originated Four Years before Latest Fiscal Year	106,013
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	5,849,888
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	9,079,409
Mortgage Finance Portfolio Segment | Special Mention
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Mortgage Finance Portfolio Segment | Substandard
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Mortgage Finance Portfolio Segment | Non-accrual
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Real Estate Portfolio Segment
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	768,716
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	1,185,276
Financing Receivable, Originated Two Years before Latest Fiscal Year	1,214,352
Financing Receivable, Originated Three Years before Latest Fiscal Year	740,292
Financing Receivable, Originated Four Years before Latest Fiscal Year	429,521
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	688,138
Financing Receivable, Revolving	635,366
Financing Receivable, Revolving, Converted To Term Loans	132,963
Gross loans held for investment	5,794,624	$ 3,444,701	$ 6,008,040
Real Estate Portfolio Segment | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Gross loans held for investment	3,686,420
Real Estate Portfolio Segment | Residential Homebuilder Finance
Financing Receivable, Recorded Investment [Line Items]
Gross loans held for investment	857,899
Real Estate Portfolio Segment | Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Gross loans held for investment	914,743
Real Estate Portfolio Segment | Secured By Family
Financing Receivable, Recorded Investment [Line Items]
Gross loans held for investment	335,562
Real Estate Portfolio Segment | Pass | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	352,688
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	892,831
Financing Receivable, Originated Two Years before Latest Fiscal Year	923,762
Financing Receivable, Originated Three Years before Latest Fiscal Year	444,587
Financing Receivable, Originated Four Years before Latest Fiscal Year	208,426
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	451,283
Financing Receivable, Revolving	62,336
Financing Receivable, Revolving, Converted To Term Loans	61,133
Gross loans held for investment	3,397,046
Real Estate Portfolio Segment | Pass | Residential Homebuilder Finance
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	162,397
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	60,077
Financing Receivable, Originated Two Years before Latest Fiscal Year	65,271
Financing Receivable, Originated Three Years before Latest Fiscal Year	3,727
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,888
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	8,483
Financing Receivable, Revolving	551,703
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	857,546
Real Estate Portfolio Segment | Pass | Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	190,995
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	150,787
Financing Receivable, Originated Two Years before Latest Fiscal Year	119,696
Financing Receivable, Originated Three Years before Latest Fiscal Year	120,817
Financing Receivable, Originated Four Years before Latest Fiscal Year	82,465
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	113,105
Financing Receivable, Revolving	16,630
Financing Receivable, Revolving, Converted To Term Loans	39,129
Gross loans held for investment	833,624
Real Estate Portfolio Segment | Pass | Secured By Family
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	58,515
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	63,031
Financing Receivable, Originated Two Years before Latest Fiscal Year	46,623
Financing Receivable, Originated Three Years before Latest Fiscal Year	54,096
Financing Receivable, Originated Four Years before Latest Fiscal Year	72,527
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	31,880
Financing Receivable, Revolving	4,697
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	331,369
Real Estate Portfolio Segment | Special Mention | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	3,475
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	11,170
Financing Receivable, Originated Two Years before Latest Fiscal Year	6,485
Financing Receivable, Originated Three Years before Latest Fiscal Year	88,633
Financing Receivable, Originated Four Years before Latest Fiscal Year	11,153
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	17,623
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	1,247
Gross loans held for investment	139,786
Real Estate Portfolio Segment | Special Mention | Residential Homebuilder Finance
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	353
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	353
Real Estate Portfolio Segment | Special Mention | Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	6,700
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,240
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	1,843
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	7,195
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	1,018
Gross loans held for investment	18,996
Real Estate Portfolio Segment | Special Mention | Secured By Family
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	646
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	635
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	1,768
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	3,049
Real Estate Portfolio Segment | Substandard | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	327
Financing Receivable, Originated Two Years before Latest Fiscal Year	47,708
Financing Receivable, Originated Three Years before Latest Fiscal Year	11,601
Financing Receivable, Originated Four Years before Latest Fiscal Year	32,645
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	30,766
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	15,940
Gross loans held for investment	138,987
Real Estate Portfolio Segment | Substandard | Residential Homebuilder Finance
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Real Estate Portfolio Segment | Substandard | Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	2,567
Financing Receivable, Originated Three Years before Latest Fiscal Year	14,452
Financing Receivable, Originated Four Years before Latest Fiscal Year	3,301
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	14,453
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	34,773
Real Estate Portfolio Segment | Substandard | Secured By Family
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	817
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	109
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	926
Real Estate Portfolio Segment | Non-accrual | Commercial Real Estate
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,749
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	4,852
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	10,601
Real Estate Portfolio Segment | Non-accrual | Residential Homebuilder Finance
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	0
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	0
Real Estate Portfolio Segment | Non-accrual | Other Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	927
Financing Receivable, Originated Four Years before Latest Fiscal Year	5,524
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	6,403
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	14,496
Gross loans held for investment	27,350
Real Estate Portfolio Segment | Non-accrual | Secured By Family
Financing Receivable, Recorded Investment [Line Items]
Financing Receivable, Originated in Current Fiscal Year	0
Financing Receivable, Year Two, Originated, Fiscal Year before Current Fiscal Year	0
Financing Receivable, Originated Two Years before Latest Fiscal Year	0
Financing Receivable, Originated Three Years before Latest Fiscal Year	0
Financing Receivable, Originated Four Years before Latest Fiscal Year	0
Financing Receivable, Originated Five or More Years before Latest Fiscal Year	218
Financing Receivable, Revolving	0
Financing Receivable, Revolving, Converted To Term Loans	0
Gross loans held for investment	$ 218

Loans Held for Investment and_5

Loans Held for Investment and Allowance for Loan Losses - Allowance Activity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	$ 195,047	$ 191,522
Provision for Loan and Lease Losses	249,769	77,794
Financing Receivable, Allowance for Credit Loss, Writeoff	207,062	77,639
Financing Receivable, Allowance for Credit Loss, Recovery	8,276	3,370
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	198,786	74,269
Allowance for credit losses, ending balance	254,615	195,047
Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	8,585
Allowance for credit losses, ending balance		8,585
Commercial Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	102,254	96,814
Provision for Loan and Lease Losses	58,630	46,738
Financing Receivable, Allowance for Credit Loss, Writeoff	73,360	44,352
Financing Receivable, Allowance for Credit Loss, Recovery	1,277	3,054
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	72,083	41,298
Allowance for credit losses, ending balance	73,061	102,254
Commercial Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	(15,740)
Allowance for credit losses, ending balance		(15,740)
Energy Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	60,253	34,882
Provision for Loan and Lease Losses	126,180	57,680
Financing Receivable, Allowance for Credit Loss, Writeoff	133,522	32,625
Financing Receivable, Allowance for Credit Loss, Recovery	6,999	316
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	126,523	32,309
Allowance for credit losses, ending balance	84,064	60,253
Energy Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	24,154
Allowance for credit losses, ending balance		24,154
Mortgage Finance Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	2,265	0
Provision for Loan and Lease Losses	403	2,265
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0
Financing Receivable, Allowance for Credit Loss, Recovery	0	0
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	0	0
Allowance for credit losses, ending balance	4,699	2,265
Mortgage Finance Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	2,031
Allowance for credit losses, ending balance		2,031
Real Estate Portfolio Segment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	30,275	52,595
Provision for Loan and Lease Losses	64,556	(21,658)
Financing Receivable, Allowance for Credit Loss, Writeoff	180	662
Financing Receivable, Allowance for Credit Loss, Recovery	0	0
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	180	662
Allowance for credit losses, ending balance	92,791	30,275
Real Estate Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	(1,860)
Allowance for credit losses, ending balance		(1,860)
Unallocated Financing Receivables
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	0	7,231
Provision for Loan and Lease Losses	0	(7,231)
Financing Receivable, Allowance for Credit Loss, Writeoff	0	0
Financing Receivable, Allowance for Credit Loss, Recovery	0	0
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)	0	0
Allowance for credit losses, ending balance	0	0
Unallocated Financing Receivables | Cumulative Effect, Period of Adoption, Adjustment
Allowance for Loan and Lease Losses [Roll Forward]
Allowance for credit losses, beginning balance	$ 0
Allowance for credit losses, ending balance		$ 0

Loans Held for Investment and_6

Loans Held for Investment and Allowance for Loan Losses - Additional Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020USD ($)loan	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2020USD ($)loan	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jan. 01, 2020USD ($)
Financing Receivable, Allowance for Credit Losses [Line Items]
Nonaccrual loans that met the criteria for restructured	$ 45,400				$ 35,100				$ 45,400	$ 35,100
Gross loans held for investment	24,501,830				24,736,642				24,501,830	24,736,642
Allowance for credit losses on off-balance sheet exposures	17,434				8,640				17,434	8,640	$ 11,434	$ 8,640
Beginning balance	$ 32,000	$ 30,000	$ 100,000	$ 96,000	17,000	$ 11,000	$ 27,000	$ 20,000	258,000	75,000	$ 87,000
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)									$ 198,786	74,269
Temporary Modification [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Aggregate Number of Contracts | loan	483								483
Financing Receivable, Modifications, Outstanding Balance	$ 1,300,000								$ 1,300,000
Financing Receivable, Modifications, Aggregate Interest Deferred	$ 7,700								$ 7,700
Continuing Modification [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Aggregate Number of Contracts | loan	48								48
Financing Receivable, Modifications, Outstanding Balance	$ 90,200								$ 90,200
Second Modification [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Modifications, Outstanding Balance	50,700								50,700
Criticized [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment	918,400				584,100				918,400	584,100
Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance For Credit Losses, Including Off-Balance Sheet Liabilities				9,100
Allowance for credit losses on off-balance sheet exposures				$ 563	563					563		563
Beginning balance									258,000	75,000
Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment	8,861,580				9,133,444				8,861,580	9,133,444		10,230,828
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)									72,083	41,298
Commercial Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment												(1,097,384)
Energy Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment	766,217				1,425,309				766,217	1,425,309
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)									126,523	32,309
Energy Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment												1,425,309
Mortgage Finance Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment	9,079,409				8,169,849				9,079,409	8,169,849		8,169,849
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)									0	0
Mortgage Finance Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment												0
Real Estate Portfolio Segment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment	$ 5,794,624				$ 6,008,040				5,794,624	6,008,040		3,444,701
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)									$ 180	662
Real Estate Portfolio Segment | Cumulative Effect, Period of Adoption, Adjustment
Financing Receivable, Allowance for Credit Losses [Line Items]
Gross loans held for investment												$ 2,563,339
Leveraged Lending
Financing Receivable, Allowance for Credit Losses [Line Items]
Financing Receivable, Allowance for Credit Loss, Period Increase (Decrease)										$ 74,300

Loans Held for Investment and_7

Loans Held for Investment and Allowance for Loan Losses - Collateral Dependent (Details) $ in Thousands	Dec. 31, 2020USD ($)
Business Assets
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	$ 3,361
Real Property
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	15,991
Oil/Gas Mineral Reserves
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	5,156
Rolling Stock
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	774
U.S. Government Guaranty
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	25,282
Commercial Portfolio Segment | Business Assets
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	3,361
Commercial Portfolio Segment | Real Property
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Commercial Portfolio Segment | Oil/Gas Mineral Reserves
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Commercial Portfolio Segment | Rolling Stock
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	774
Commercial Portfolio Segment | U.S. Government Guaranty
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	4,135
Energy Portfolio Segment | Business Assets
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Energy Portfolio Segment | Real Property
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Energy Portfolio Segment | Oil/Gas Mineral Reserves
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	5,156
Energy Portfolio Segment | Rolling Stock
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Energy Portfolio Segment | U.S. Government Guaranty
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	5,156
Real Estate Portfolio Segment | Commercial Real Estate | Business Assets
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Commercial Real Estate | Real Property
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	4,619
Real Estate Portfolio Segment | Commercial Real Estate | Oil/Gas Mineral Reserves
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Commercial Real Estate | Rolling Stock
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Commercial Real Estate | U.S. Government Guaranty
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	4,619
Real Estate Portfolio Segment | Other | Business Assets
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Other | Real Property
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	11,372
Real Estate Portfolio Segment | Other | Oil/Gas Mineral Reserves
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Other | Rolling Stock
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	0
Real Estate Portfolio Segment | Other | U.S. Government Guaranty
Financing Receivable, Recorded Investment, Past Due [Line Items]
Collateral-dependent Loans	$ 11,372

Loans Held for Investment and_8

Loans Held for Investment and Allowance for Loan Losses - Age Analysis (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 31,308
Non-accrual(2)	121,989	$ 225,400
Current	24,348,533
Total	24,501,830		$ 24,736,642
Non-accrual With No Allowance	43,688
Premium finance loans past due and still accruing	6,400
Interest Income Reversed	1,300
Commercial Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	18,098
Non-accrual(2)	32,096	88,600
Current	8,811,386
Total	8,861,580	10,230,828	9,133,444
Non-accrual With No Allowance	6,917
Energy Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Non-accrual(2)	51,724	125,000
Current	714,493
Total	766,217		1,425,309
Non-accrual With No Allowance	17,759
Mortgage Finance Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Non-accrual(2)	0
Current	9,079,409
Total	9,079,409	8,169,849	8,169,849
Non-accrual With No Allowance	0
Real Estate Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total	5,794,624	3,444,701	$ 6,008,040
Real Estate Portfolio Segment | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,223
Non-accrual(2)	10,601	9,400
Current	3,672,596
Total	3,686,420
Non-accrual With No Allowance	5,749
Real Estate Portfolio Segment | Residential Homebuilder Finance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Non-accrual(2)	0
Current	857,899
Total	857,899
Non-accrual With No Allowance	0
Real Estate Portfolio Segment | Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,964
Non-accrual(2)	27,350	881
Current	883,429
Total	914,743
Non-accrual With No Allowance	13,263
Real Estate Portfolio Segment | Secured By Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	6,023
Non-accrual(2)	218	$ 1,400
Current	329,321
Total	335,562
Non-accrual With No Allowance	0
30 to 59 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	13,908
30 to 59 Days Past Due | Commercial Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	6,171
30 to 59 Days Past Due | Energy Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
30 to 59 Days Past Due | Mortgage Finance Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
30 to 59 Days Past Due | Real Estate Portfolio Segment | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,926
30 to 59 Days Past Due | Real Estate Portfolio Segment | Residential Homebuilder Finance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
30 to 59 Days Past Due | Real Estate Portfolio Segment | Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	3,471
30 to 59 Days Past Due | Real Estate Portfolio Segment | Secured By Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,340
60 to 89 Days Past Due
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	4,859
60 to 89 Days Past Due | Commercial Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	2,602
60 to 89 Days Past Due | Energy Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
60 to 89 Days Past Due | Mortgage Finance Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
60 to 89 Days Past Due | Real Estate Portfolio Segment | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	297
60 to 89 Days Past Due | Real Estate Portfolio Segment | Residential Homebuilder Finance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
60 to 89 Days Past Due | Real Estate Portfolio Segment | Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	493
60 to 89 Days Past Due | Real Estate Portfolio Segment | Secured By Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	1,467
Greater Than 90 Days
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	12,541
Greater Than 90 Days | Commercial Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	9,325
Greater Than 90 Days | Energy Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Greater Than 90 Days | Mortgage Finance Portfolio Segment
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Greater Than 90 Days | Real Estate Portfolio Segment | Commercial Real Estate
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Greater Than 90 Days | Real Estate Portfolio Segment | Residential Homebuilder Finance
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Greater Than 90 Days | Real Estate Portfolio Segment | Other Financing Receivable
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	0
Greater Than 90 Days | Real Estate Portfolio Segment | Secured By Family
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due	$ 3,216

Loans Held for Investment and_9

Loans Held for Investment and Allowance for Loan Losses - Details of Recorded Investment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)loan	Dec. 31, 2019USD ($)loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	8	5
Loans modified as restructured loans | $	$ 40,526	$ 26,881
Extended maturity
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	3	2
Loans modified as restructured loans | $	$ 13,095	$ 5,688
Adjusted payment schedule
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	5	3
Loans modified as restructured loans | $	$ 27,431	$ 21,193
Commercial | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	4	4
Loans modified as restructured loans | $	$ 21,886	$ 22,946
Commercial | Extended maturity | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	2	1
Loans modified as restructured loans | $	$ 7,390	$ 1,753
Commercial | Adjusted payment schedule | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	2	3
Loans modified as restructured loans | $	$ 14,496	$ 21,193
Energy loans | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	4	1
Loans modified as restructured loans | $	$ 18,640	$ 3,935
Energy loans | Extended maturity | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	1	1
Loans modified as restructured loans | $	$ 5,705	$ 3,935
Energy loans | Adjusted payment schedule | Commercial Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts | loan	3	0
Loans modified as restructured loans | $	$ 12,935	$ 0

Certain Transfers of Financia_3

Certain Transfers of Financial Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Outstanding balance(1):
Beginning balance	$ 2,568,362	$ 1,949,785
Loans purchased	11,366,986	10,183,057
Payments and loans sold	(13,654,211)	(9,564,480)
Ending balance	281,137	2,568,362
Fair value adjustment:
Beginning balance	8,772	19,689
Increase/(decrease) to fair value	(6,744)	(10,917)
Ending balance	2,028	8,772
Loans held for sale	283,165	2,577,134
Small Business Administration Loans [Member]
Fair value adjustment:
Beginning balance	5,800	299
Ending balance	$ 44,100	$ 5,800

Certain Transfers of Financia_4

Certain Transfers of Financial Assets (Details 1) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Loans held for sale	$ 281,137,000	$ 2,568,362,000	$ 1,949,785,000
Estimated exposure related to servicing assets	621,000	3,600,000
Principal amount outstanding of loans in servicing portfolio	13,800,000,000	6,700,000,000
Escrow deposits related to servicing portfolio	152,600,000	63,700,000
Losses due to repurchase indemnification and make-whole obligations	8,400,000	9,000,000
Total Past Due	31,308,000
Greater Than 90 Days
Loans and Leases Receivable Disclosure [Line Items]
Loans held for sale	16,700,000	8,200,000
Total Past Due	12,541,000
Mortgage servicing rights
Loans and Leases Receivable Disclosure [Line Items]
Impairment charges	20,200,000	5,800,000
Government guarantees | Greater Than 90 Days
Loans and Leases Receivable Disclosure [Line Items]
Loans held for sale	3,300,000	6,000,000
Government guarantees | Maturity Greater than 90 Days [Member] | Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Loans and Leases Receivable Disclosure [Line Items]
Total Past Due	13,400,000	1,900,000
Nonperforming Financial Instruments
Loans and Leases Receivable Disclosure [Line Items]
Loans held for sale	$ 7,000,000	$ 0

Certain Transfers of Financia_5

Certain Transfers of Financial Assets (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Valuation Allowance for Impairment of Recognized Servicing Assets, Sales and Disposals [Abstract]
Valuation allowance, beginning balance	$ 3,600
Valuation allowance, ending balance	621	$ 3,600
Mortgage Servicing Rights
Servicing Asset at Amortized Cost, Balance [Roll Forward]
Balance, beginning of year	70,707	42,474
Capitalized servicing rights	99,678	39,774
Amortization	(38,994)	(11,541)
Sales	0	0
Balance, end of period	131,391	70,707
Valuation Allowance for Impairment of Recognized Servicing Assets, Sales and Disposals [Abstract]
Valuation allowance, beginning balance	5,803	0
Increase (decrease) in valuation allowance	20,164	5,803
Valuation allowance, ending balance	25,967	5,803
MSRs, net	105,424	64,904
Fair value	$ 105,424	$ 64,904

Certain Transfers of Financia_6

Certain Transfers of Financial Assets (Details 3) - Mortgage Servicing Rights	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Average discount rates (percent)	9.09%	9.06%
Expected prepayment speeds (percent)	16.37%	13.11%
Weighted-average life, in years	4 years 10 months 24 days	5 years 9 months 18 days

Certain Transfers of Financia_7

Certain Transfers of Financial Assets Certain Transfers of Financial Assets (Details 4) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Transfers and Servicing [Abstract]
50 bp adverse change in prepayment speed	$ (12,203)	$ (10,768)
100 bp adverse change in prepayment speed	$ (16,062)	$ (17,965)

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
ROU asset	$ 67,000	$ 80,000
Lease liability	$ 82,529	$ 95,900
Minimum
Lessee, Lease, Description [Line Items]
Term of lease contract	5 years
Minimum | Office Space and Bank Branches
Lessee, Lease, Description [Line Items]
Term of lease contract	1 year
Maximum
Lessee, Lease, Description [Line Items]
Term of lease contract	10 years
Maximum | Office Space and Bank Branches
Lessee, Lease, Description [Line Items]
Term of lease contract	13 years

Leases - Net lease cost (Detail

Leases - Net lease cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 15,544	$ 14,844
Short-term lease cost	19	19
Variable lease cost	4,476	3,918
Sublease income	(107)	(126)
Net lease cost	19,932	18,655
Operating cash flows from operating leases	16,568	14,711
Non-cash changes in ROU assets	765	98,369
Non-cash changes in lease liabilities	784	108,189
Right-of-use asset obtained in exchange for finance lease liability	$ 833	$ 87,900

Leases - Other information (Det

Leases - Other information (Details)	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Weighted-average remaining lease term - operating leases, in years	6 years 6 months	7 years 2 months 12 days
Weighted-average discount rate - operating leases	2.74%	2.75%

Leases - Maturity of remaining

Leases - Maturity of remaining lease liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
2021	$ 17,222
2022	16,455
2023	16,511
2024	11,754
2025	5,524
2026 and thereafter	22,849
Total lease payments	90,315
Less: Interest	(7,786)
Present value of lease liabilities	$ 82,529	$ 95,900

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill
Gross	$ 15,468	$ 15,468
Accumulated Amortization	(374)	(374)
Net	15,094	15,094
Intangible assets—customer relationships and trademarks
Gross	9,006	9,006
Accumulated Amortization	(6,433)	(6,001)
Net	2,573	3,005
Total goodwill and intangible assets
Gross	24,474	24,474
Accumulated Amortization	(6,807)	(6,375)
Net	$ 17,667	$ 18,099

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets (Details 1) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
2016	$ 405
2017	405
2018	382
2019	268
2020	268
Thereafter	845
Net	$ 2,573	$ 3,005

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets (Details 2) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Total intangible assets	$ 17,667	$ 18,099
Amortization expense related to intangible assets	$ 432	$ 471	$ 470

Premises and Equipment (Details

Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of premises and equipment
Premises and equipment, gross	$ 73,858	$ 72,357
Accumulated depreciation	(49,312)	(41,145)
Total premises and equipment, net	24,546	31,212
Depreciation, Depletion and Amortization
Depreciation expense	9,500	9,200	$ 9,000
Premises
Summary of premises and equipment
Premises and equipment, gross	32,231	30,181
Furniture and equipment
Summary of premises and equipment
Premises and equipment, gross	$ 41,627	$ 42,176

Deposits (Details)

Deposits (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Non-interest bearing deposits
Non-interest-bearing demand deposits	$ 12,740,947	$ 9,438,459
Interest-bearing deposits:
Transaction	4,396,243	3,651,128
Savings	11,619,880	10,517,975
Time	2,239,519	2,871,031
Total interest-bearing deposits	18,255,642	17,040,134
Total deposits	$ 30,996,589	$ 26,478,593

Deposits (Details 1)

Deposits (Details 1) $ in Thousands	Dec. 31, 2020USD ($)
Scheduled maturities of interest bearing time deposits
2021	$ 1,317,558
2022	795,656
2023	121,376
2024	1,921
2025	3,003
2026 and after	5
Interest bearing time deposits, total	$ 2,239,519

Deposits (Details 2)

Deposits (Details 2) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deposits [Abstract]
Interest-bearing time deposits of $250,000 or more	$ 386.9	$ 347.7

Short-Term and Other Borrowin_3

Short-Term and Other Borrowings (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Federal funds purchased
Debt Instrument [Line Items]
Amount outstanding at year-end	$ 107,600	$ 132,270	$ 629,169
Interest rate at year-end	0.15%	1.66%	2.54%
Average balance outstanding during the year	$ 207,121	$ 502,604	$ 323,140
Weighted-average interest rate during the year	0.52%	2.36%	2.02%
Maximum outstanding at any month end	$ 300,430	$ 905,473	$ 629,169
Customer repurchase agreements
Debt Instrument [Line Items]
Amount outstanding at year-end	$ 4,151	$ 9,496	$ 12,005
Interest rate at year-end	0.35%	0.61%	0.09%
Average balance outstanding during the year	$ 5,563	$ 11,655	$ 9,812
Weighted-average interest rate during the year	0.47%	0.51%	0.09%
Maximum outstanding at any month end	$ 8,314	$ 14,208	$ 13,835
FHLB borrowings
Debt Instrument [Line Items]
Amount outstanding at year-end	$ 3,000,000	$ 2,400,000	$ 3,900,000
Interest rate at year-end	0.46%	1.68%	2.56%
Average balance outstanding during the year	$ 2,902,732	$ 2,523,836	$ 1,769,452
Weighted-average interest rate during the year	0.72%	2.31%	2.05%
Maximum outstanding at any month end	$ 4,900,000	$ 5,000,000	$ 4,000,000

Short-Term and Other Borrowin_4

Short-Term and Other Borrowings (Details 1) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of other borrowing capacities
Total FHLB borrowing capacity	$ 10,599,856,000	$ 8,964,608,000	$ 4,569,563,000
Unused federal funds lines available from commercial banks	1,030,000,000	1,432,000,000	620,000,000
Unused Federal Reserve borrowings capacity	2,179,000,000	3,637,238,000	4,933,965,000
Unused revolving line of credit	130,000,000	130,000,000	130,000,000
Average amount oustanding	0	0	0
FHLB borrowing capacity relating to loans
Summary of other borrowing capacities
Total FHLB borrowing capacity	7,653,317,000	8,964,019,000	4,568,842,000
FHLB borrowing capacity relating to securities
Summary of other borrowing capacities
Total FHLB borrowing capacity	$ 2,946,539,000	$ 589,000	$ 721,000

Long-Term Debt (Details)

Long-Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 31, 2014	Sep. 21, 2012
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 113,406	$ 113,406	$ 175,000	$ 111,000
Stated interest rate			5.25%	6.50%
Texas Capital Bancshares Statutory Trust I
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 10,310
Texas Capital Bancshares Statutory Trust I | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.35%
Texas Capital Statutory Trust II
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 10,310
Texas Capital Statutory Trust II | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.25%
Texas Capital Statutory Trust III
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 25,774
Texas Capital Statutory Trust III | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.51%
Texas Capital Statutory Trust IV
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 25,774
Texas Capital Statutory Trust IV | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.60%
Texas Capital Statutory Trust V
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 41,238
Texas Capital Statutory Trust V | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.71%
Trust preferred subordinated debentures
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Total borrowings	$ 113,400
Trust preferred subordinated debentures | Texas Capital Bancshares Statutory Trust I | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.35%
Trust preferred subordinated debentures | Texas Capital Statutory Trust II | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.25%
Trust preferred subordinated debentures | Texas Capital Statutory Trust III | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.51%
Trust preferred subordinated debentures | Texas Capital Statutory Trust IV | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.60%
Trust preferred subordinated debentures | Texas Capital Statutory Trust V | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.71%

Long-Term Debt (Details 1)

Long-Term Debt (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Jan. 31, 2014	Sep. 21, 2012
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 113,406	$ 113,406	$ 175,000	$ 111,000
Texas Capital Bancshares Statutory Trust I
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 10,310
Texas Capital Bancshares Statutory Trust I | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.35%
Texas Capital Statutory Trust II
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 10,310
Texas Capital Statutory Trust II | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	3.25%
Texas Capital Statutory Trust III
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 25,774
Texas Capital Statutory Trust III | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.51%
Texas Capital Statutory Trust IV
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 25,774
Texas Capital Statutory Trust IV | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.60%
Texas Capital Statutory Trust V
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Trust preferred securities issued	$ 41,238
Texas Capital Statutory Trust V | LIBOR
Financial Instruments Subject to Mandatory Redemption by Settlement Terms [Line Items]
Interest rate on subordinated debentures, spread on variable rate	1.71%

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal									$ 32,701	$ 69,427	$ 82,556
State									920	4,072	3,808
Total									33,621	73,499	86,364
Deferred:
Federal									(7,964)	10,796	(6,400)
State									0	0	0
Total									(7,964)	10,796	(6,400)
Total expense:
Federal									24,737	80,223	76,156
State									920	4,072	3,808
Income tax expense	$ 22,834	$ 15,060	$ (7,606)	$ (4,631)	$ 16,539	$ 23,958	$ 21,387	$ 22,411	$ 25,657	$ 84,295	$ 79,964

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amount
U.S. statutory rate									$ 19,309	$ 85,504	$ 79,965
State taxes									726	3,217	3,008
Tax-exempt income									(3,356)	(5,127)	(4,855)
Tax credits									(1,216)	(2,052)	(2,421)
Disallowed FDIC									3,920	2,468	2,418
Disallowed compensation									3,098	628	400
Other									3,176	(343)	1,449
Income tax expense	$ 22,834	$ 15,060	$ (7,606)	$ (4,631)	$ 16,539	$ 23,958	$ 21,387	$ 22,411	$ 25,657	$ 84,295	$ 79,964
Rate
U.S. statutory rate									21.00%	21.00%	21.00%
State taxes									1.00%	1.00%	1.00%
Tax-exempt income									(4.00%)	(1.00%)	(1.00%)
Tax credits									(1.00%)	(1.00%)	(1.00%)
Disallowed FDIC									4.00%	1.00%	1.00%
Disallowed compensation									3.00%	0.00%	0.00%
Other									4.00%	0.00%	0.00%
Effective tax rate									28.00%	21.00%	21.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Unrecognized Tax Benefits	$ 1,100	$ 1,300	$ 1,600
Allowance for credit losses	$ 59,279	44,383
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for credit losses		$ 2,000

Income Taxes - Deferred Tax Ass

Income Taxes - Deferred Tax Asset (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Deferred tax assets:
Allowance for credit losses	$ 59,279		$ 44,383
Operating lease liabilities	17,983		20,894
Loan origination fees	11,181		10,638
Stock compensation	3,913		3,605
Non-accrual interest	1,245		2,351
Non-qualified deferred compensation	5,795		4,027
Other	3,136		2,544
Total deferred tax assets	102,532		88,442
Deferred tax liabilities:
Loan origination costs	(2,997)		(2,686)
Leases	(8,603)		(7,912)
Operating lease ROU assets	(16,617)		(19,644)
MSRs	(22,566)		(13,818)
Depreciation	(14,968)		(17,602)
Unrealized gain on securities	(4,193)		(2,379)
Other	(3,381)		(3,337)
Total deferred tax liabilities	(73,325)		(67,378)
Net deferred tax asset	$ 29,207	$ 21,064	$ 21,064

Financial Instruments with Of_3

Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance of allowance for off-balance sheet credit losses	$ 8,640	$ 11,434
Provision for off-balance sheet credit losses	8,231	(2,794)
Ending balance of allowance for off-balance sheet credit losses	17,434	8,640
Cumulative Effect, Period of Adoption, Adjustment
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Beginning balance of allowance for off-balance sheet credit losses	563
Ending balance of allowance for off-balance sheet credit losses		563
Commitments to extend credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	8,530,453	8,066,655
Standby letters of credit
Allowance For Off-Balance Sheet Credit Losses [Roll Forward]
Off-balance sheet liability	$ 268,894	$ 261,405

Regulatory Restrictions (Detail

Regulatory Restrictions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2009USD ($)
Broker-Dealer, Net Capital Requirement, SEC Regulation [Abstract]
Required reserve balance at the Federal Reserve		$ 283,400
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Mortgage finance(1)	$ 9,079,409	8,169,849
Mortgage Finance, Average Balance	9,600,000
Assets	37,726,096	32,548,069	$ 15,000,000
Common Equity Tier 1 [Abstract]
CET1, actual amount	2,708,150	2,653,999
Total capital (to risk-weighted assets):
Total capital (to risk weighted assets), actual amount	3,498,737	3,398,345
Tier 1 capital (to risk-weighted assets):
Tier 1 capital (to risk-weighted assets), actual amount	2,968,150	2,912,529
Tier 1 capital (to average assets):
Tier 1 capital (to average assets), actual amount	$ 2,968,150	$ 2,912,529
Risk Based Ratios [Abstract]
CET1, actual ratio	9.35%	8.88%
Total capital (to risk weighted assets), actual ratio	0.1209	0.1137
Tier 1 capital (to risk-weighted assets), actual ratio	0.1025	0.0975
Tier 1 capital (to average assets), actual ratio	0.0752	0.0842
Bank
Common Equity Tier 1 [Abstract]
CET1, actual amount	$ 2,744,211	$ 2,676,513
CET1 to be well capitalized under prompt corrective action provisions, amount	1,880,745	1,941,522
Total capital (to risk-weighted assets):
Total capital (to risk weighted assets), actual amount	3,375,983	3,262,144
Total capital (to risk weighted assets) to be well capitalized under prompt corrective action provisions, amount	2,893,453	2,986,957
Tier 1 capital (to risk-weighted assets):
Tier 1 capital (to risk-weighted assets), actual amount	2,904,211	2,835,043
Tier 1 capital (to risk weighted assets) to be well capitalized under prompt corrective action provisions, amount	2,314,763	2,389,565
Tier 1 capital (to average assets):
Tier 1 capital (to average assets), actual amount	2,904,211	2,835,043
Tier 1 capital (to average assets) to be well capitalized under prompt corrective action provisions, amount	$ 1,972,758	$ 1,728,988
Risk Based Ratios [Abstract]
CET1, actual ratio	9.48%	8.96%
CET1 to be well capitalized under prompt corrective action provisions, ratio	6.50%	6.50%
Total capital (to risk weighted assets), actual ratio	0.1167	0.1092
Total capital (to risk weighted assets) to be well capitalized under prompt corrective action provisions, ratio	0.1000	0.1000
Tier 1 capital (to risk-weighted assets), actual ratio	0.1004	0.0949
Tier 1 capital (to risk weighted assets) to be well capitalized under prompt corrective action provisions, ratio	0.0800	0.0800
Tier 1 capital (to average assets), actual ratio	0.0736	0.0820
Tier 1 capital (to average assets) to be well capitalized under prompt corrective action provisions, ratio	0.0500	0.0500
Basel III, Phase-In Schedule
Common Equity Tier 1 [Abstract]
CET1 for capital adequacy purposes, amount	$ 2,026,400	$ 2,091,591
Total capital (to risk-weighted assets):
Total capital (to risk weighted assets) for capital adequacy purposes, amount	3,039,600	3,137,926
Tier 1 capital (to risk-weighted assets):
Tier 1 capital (to risk-weighted assets) for capital adequacy purposes, amount	2,460,628	2,540,226
Tier 1 capital (to average assets):
Tier 1 capital (to average assets) for capital adequacy purposes, amount	$ 1,578,651	$ 1,383,640
Risk Based Ratios [Abstract]
CET1 for capital adequacy purposes, ratio	7.00%	7.00%
Total capital (to risk weighted assets) for capital adequacy purposes, ratio	0.1050	0.1050
Tier 1 capital (to risk-weighted assets) for capital adequacy purposes, ratio	0.0850	0.0850
Tier 1 capital (to average assets) for capital adequacy purposes, ratio	0.0400	0.0400
Basel III, Phase-In Schedule | Bank
Common Equity Tier 1 [Abstract]
CET1 for capital adequacy purposes, amount	$ 2,025,417	$ 2,090,870
Total capital (to risk-weighted assets):
Total capital (to risk weighted assets) for capital adequacy purposes, amount	3,038,126	3,136,305
Tier 1 capital (to risk-weighted assets):
Tier 1 capital (to risk-weighted assets) for capital adequacy purposes, amount	2,459,435	2,538,913
Tier 1 capital (to average assets):
Tier 1 capital (to average assets) for capital adequacy purposes, amount	$ 1,578,207	$ 1,383,190
Risk Based Ratios [Abstract]
CET1 for capital adequacy purposes, ratio	7.00%	7.00%
Total capital (to risk weighted assets) for capital adequacy purposes, ratio	0.1050	0.1050
Tier 1 capital (to risk-weighted assets) for capital adequacy purposes, ratio	0.0850	0.0850
Tier 1 capital (to average assets) for capital adequacy purposes, ratio	0.0400	0.0400
Basel III, Phased-In
Risk Based Ratios [Abstract]
Tier 1 capital (to average assets) to be well capitalized under prompt corrective action provisions, ratio	0.025

Stock-Based Compensation and _3

Stock-Based Compensation and Employee Benefits (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer contribution	$ 10,300,000	$ 9,500,000	$ 9,600,000
Employer discretionary contributions	$ 1,000,000	1,000,000	1,000,000
Eligible employee contribution, minimum (in percent)	1.00%
Eligible employee contribution, maximum (in percent)	10.00%
Number of shares authorized under the plan	2,550,000
Number of shares available to be issued under the plan	1,203,294
Compensation expense	$ 26,000	36,000	62,000
Compensation cost for all share-based arrangements, net of taxes	15,700,000	11,800,000	9,000,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	15,655,000	11,733,000	8,803,000
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 0	$ 6,000	$ 121,000
Vesting period (in years)	5 years
Cash based performance
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of cash-based performance units outstanding	59,285
Number of cash-based performance units issued in period	0	0	138,773
Cash-based compensation expense	$ 1,800,000	$ 5,800,000	$ 8,000,000
Service based
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Minimum | Time-based RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Minimum | Time and Performance-based RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	3 years
Maximum | Time-based RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	5 years
Maximum | Time and Performance-based RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)	4 years
2006 ESPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under the plan	400,000
Number of shares purchased under the plan	155,933	155,933	143,348

Stock-Based Compensation and _4

Stock-Based Compensation and Employee Benefits (Details 3) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Additional Information:
Compensation expense	$ 26,000	$ 36,000	$ 62,000
SARs
SARs
Outstanding at beginning of year (in shares)	21,200	41,350	74,363
Exercised (in shares)	(8,800)	(20,150)	(33,013)
Outstanding at year-end (in shares)	12,400	21,200	41,350
Weighted Average Exercise Price
SARs outstanding at beginning of year, weighted average exercise price	$ 33.95	$ 29.13	$ 30.12
SARs exercised, weighted average exercise price	20.52	24.07	31.35
SARs outstanding at year end, weighted average exercise price	$ 43.48	$ 33.95	$ 29.13
Additional Information:
SARs vested and exercisable at year-end	12,400	21,200	39,750
SARs vested and exercisable at year end, weighted average exercise price	$ 43.48	$ 33.95	$ 27.81
Weighted average remaining contractual life of SARs vested (in years)	2 years 3 months 3 days	2 years 1 month 20 days	2 years 3 months 29 days
Weighted average remaining contractual life of SARs (in years)	2 years 3 months 3 days	2 years 1 month 20 days	2 years 5 months 8 days
Compensation expense	$ 0	$ 6,000	$ 121,000
Unrecognized compensation expense	$ 0	$ 0	$ 6,000
Weighted average period over which unrecognized compensation expense is expected to be recognized (in years)	0 years	0 years	2 months 1 day
Fair value of shares vested during the year	$ 0	$ 37,000	$ 211,000
Intrinsic value of SARs exercised	$ 294,000	$ 724,000	$ 1,919,000

Stock-Based Compensation and _5

Stock-Based Compensation and Employee Benefits (Details 4) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Weighted- Average Grant- Date Fair Value
Compensation expense	$ 26,000	$ 36,000	$ 62,000
RSUs
Number of Shares
Outstanding at beginning of year (in shares)	558,312	349,533	423,732
Granted (in shares)	631,092	386,913	95,891
Exercised (in shares)	(171,494)	(140,666)	(121,507)
Forfeited (in shares)	(62,316)	(37,468)	(48,583)
Outstanding at year-end (in shares)	955,594	558,312	349,533
Weighted- Average Grant- Date Fair Value
Balance at beginning of year, weighted average grant-date fair value	$ 64.95	$ 69.11	$ 60.01
Granted, weighted average grant-date fair value	39.37	59.28	88.07
RSUs exercised	65.17	59.97	54.97
Forfeited, weighted average grant-date fair value	56.92	62.73	63.60
Balance at year end, weighted average grant-date fair value	$ 48.76	$ 64.95	$ 69.11
Compensation expense	$ 15,655,000	$ 11,733,000	$ 8,803,000
Unrecognized compensation expense	$ 29,146,000	$ 25,305,000	$ 16,538,000
Weighted average period over which unrecognized compensation expense is expected to be recognized (in years)	2 years 9 months 29 days	3 years 1 month 2 days	2 years 10 months 24 days

Fair Value Disclosures (Details

Fair Value Disclosures (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	$ 3,163,138	$ 214,257
Loans held for sale	239,100	2,571,300
U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	123,589
Tax-exempt asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	199,176	197,027
CRT Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	11,417	11,964
Fair value measurements, recurring basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities	26,593	18,484
Loans held for sale	0	0
Derivative assets	0	0
Derivative liabilities	0	0
Non-qualified deferred compensation plan liabilities	26,593	18,484
Fair value measurements, recurring basis | Level 1 | U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0
Fair value measurements, recurring basis | Level 1 | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 1 | Tax-exempt asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 1 | CRT Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities	7,239	7,130
Loans held for sale	232,147	2,564,281
Derivative assets	102,720	48,684
Derivative liabilities	99,255	51,310
Non-qualified deferred compensation plan liabilities	0	0
Fair value measurements, recurring basis | Level 2 | U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	123,589
Fair value measurements, recurring basis | Level 2 | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	2,828,956	5,266
Fair value measurements, recurring basis | Level 2 | Tax-exempt asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 2 | CRT Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investment securities	0	0
Loans held for sale	6,933	7,043
Derivative assets	0	0
Derivative liabilities	0	0
Non-qualified deferred compensation plan liabilities	0	0
Fair value measurements, recurring basis | Level 3 | U.S. government agency securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0
Fair value measurements, recurring basis | Level 3 | Residential mortgage-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	0	0
Fair value measurements, recurring basis | Level 3 | Tax-exempt asset-backed securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	199,176	197,027
Fair value measurements, recurring basis | Level 3 | CRT Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities	11,417	11,964
Fair value measurements, nonrecurring basis | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	0	0
Fair value measurements, nonrecurring basis | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	0	0
Fair value measurements, nonrecurring basis | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans	$ 21,209	$ 109,585

Fair Value Disclosures (Detai_2

Fair Value Disclosures (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at Beginning of Period	$ 7,043	$ 16,415
Purchases / Additions	1,472	321
Sales / Reductions	(2,077)	(10,690)
Realized	248	190
Unrealized	247	807
Balance at End of Period	6,933	7,043
Tax-exempt asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at Beginning of Period	197,027	95,804
Purchases / Additions	8,470	92,010
Sales / Reductions	(6,755)	(4,302)
Realized	0	0
Unrealized	434	13,515
Balance at End of Period	199,176	197,027
CRT Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at Beginning of Period	11,964	0
Purchases / Additions	0	15,044
Sales / Reductions	0	0
Realized	0	(331)
Unrealized	(547)	(2,749)
Balance at End of Period	$ 11,417	$ 11,964

Fair Value Disclosures (Detai_3

Fair Value Disclosures (Details 2) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)
Tax-exempt asset-backed securities | Minimum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Term	5 years 6 months 3 days
Tax-exempt asset-backed securities | Maximum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Term	5 years 6 months 14 days
Impaired loans
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Asset measured on nonrecurring basis, reported fair value	$ 21.2	$ 109.6
Asset measured on nonrecurring basis, carrying value	25.3	145.4
Asset measured on nonrecurring basis, specific valuation allowance	$ 4.1	$ 35.8
CRT Securities | Minimum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Term	5 years 11 months 19 days
CRT Securities | Maximum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Term	10 years 6 months 14 days
Measurement Input, Discount Rate
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Asset-Backed Securities, Measurement Input	0.0249
Asset-Backed Securities, Term	5 years 6 months 10 days
Loans Held-for-sale, Measurement Input	0.972	0.941
Measurement Input, Discount Rate | Tax-exempt asset-backed securities | Minimum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.0244
Measurement Input, Discount Rate | Tax-exempt asset-backed securities | Maximum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.0253
Measurement Input, Discount Rate | Tax-exempt asset-backed securities | Weighted Average
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input		0.0299
Debt Securities, Available-for-sale, Term		7 years
Measurement Input, Discount Rate | CRT Securities | Minimum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.0275
Measurement Input, Discount Rate | CRT Securities | Maximum
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.0759
Measurement Input, Discount Rate | CRT Securities | Weighted Average
Fair Value Assets Measured On Non Recurring Basis Unobservable Input Reconciliation [Line Items]
Debt Securities, Available-for-sale, Measurement Input	0.0436	0.0454
Debt Securities, Available-for-sale, Term	7 years 5 months 26 days	9 years 3 months 29 days

Fair Value Disclosures (Detai_4

Fair Value Disclosures (Details 3) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	$ 3,163,138	$ 214,257
Loans held for sale	239,100	2,571,300
Subordinated notes	282,490	282,129
Level 1 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	26,593	18,484
Level 1 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	9,206,380	4,425,583
Debt securities	26,593	18,484
Level 2 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	2,959,784	12,396
Loans held for sale	232,147	2,570,091
Derivative assets	102,720	48,684
Federal funds purchased	107,600	132,270
Customer repurchase agreements	4,151	9,496
Other borrowings	3,000,000	2,400,000
Subordinated notes	282,490	282,129
Derivative liabilities	99,255	51,310
Level 2 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	2,959,784	12,396
Loans held for sale	232,147	2,570,091
Derivative assets	102,720	48,684
Federal funds purchased	107,600	132,270
Customer repurchase agreements	4,151	9,496
Other borrowings	3,000,000	2,400,000
Subordinated notes	291,704	292,302
Derivative liabilities	99,255	51,310
Level 3 | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	210,593	208,991
Loans held for sale	6,933	7,043
Loans held for investment, net	24,176,245	24,451,215
Deposits	30,996,589	26,478,593
Trust preferred subordinated debentures	113,406	113,406
Level 3 | Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt securities	210,593	208,991
Loans held for sale	6,933	7,043
Loans held for investment, net	24,233,185	24,478,586
Deposits	30,997,980	26,486,090
Trust preferred subordinated debentures	$ 113,406	$ 113,406

Parent Company Only (Details)

Parent Company Only (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 31, 2014	Sep. 21, 2012	Dec. 31, 2009
Assets
Loans held for investment (net of unearned income)	$ 15,351,451		$ 16,476,413
Other assets	715,699		740,051
Total assets	37,726,096		32,548,069						$ 15,000,000
Liabilities and Stockholders’ Equity
Subordinated notes, net	282,490		282,129
Trust preferred subordinated debentures	113,406		113,406				$ 175,000	$ 111,000
Total liabilities	34,854,872		29,746,748	$ 25,777,459	$ 22,885,573
Preferred stock	150,000		150,000
Common stock	504		503
Additional paid-in capital	991,898		978,205
Retained earnings	1,713,056	$ 1,663,671	1,663,671	1,361,406	1,077,851	$ 891,520
Treasury stock	(8)		(8)
Accumulated other comprehensive income	15,774		8,950
Total stockholders’ equity	2,871,224		2,801,321	2,480,308	2,190,072	$ 1,997,890
Total liabilities and stockholders’ equity	37,726,096		32,548,069
Texas Capital Bancshares, Inc.
Assets
Cash and cash equivalents	57,472		71,462	$ 89,561	$ 144,635
Loans held for investment (net of unearned income)	7,500		10,500
Investment in subsidiaries	2,930,843		2,847,393
Other assets	89,551		88,639
Total assets	3,085,366		3,017,994
Liabilities and Stockholders’ Equity
Other liabilities	1,320		1,768
Subordinated notes, net	108,816		108,715
Trust preferred subordinated debentures	113,406		113,406
Total liabilities	223,542		223,889
Preferred stock	150,000		150,000
Common stock	504		503
Additional paid-in capital	1,002,050		988,357
Retained earnings	1,693,504		1,646,303
Treasury stock	(8)		(8)
Accumulated other comprehensive income	15,774		8,950
Total stockholders’ equity	2,861,824		2,794,105
Total liabilities and stockholders’ equity	$ 3,085,366		$ 3,017,994

Parent Company Only (Details 1)

Parent Company Only (Details 1) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Earnings
Interest on loans									$ 1,011,175	$ 1,284,036	$ 1,124,970
Other non-interest income									27,238	45,005	26,559
Interest expense	$ 32,153	$ 36,162	$ 42,082	$ 77,689	$ 89,372	$ 102,933	$ 103,340	$ 89,947	188,086	385,592	249,333
Salaries and employee benefits									340,529	328,483	300,899	$ 266,461
Legal and professional									52,132	52,460	42,990
Other non-interest expense									41,809	44,701	49,670	48,048
Income tax expense	22,834	15,060	(7,606)	(4,631)	16,539	23,958	21,387	22,411	25,657	84,295	79,964
Net income	60,176	57,116	(34,316)	(16,687)	64,420	88,082	77,812	81,701	66,289	312,015	293,387	196,081
Preferred stock dividends	2,437	2,438	2,437	2,438	2,437	2,438	2,437	2,438	9,750	9,750	9,750
Net income/(loss) available to common stockholders	$ 57,739	$ 54,678	$ (36,753)	$ (19,125)	$ 61,983	$ 85,644	$ 75,375	$ 79,263	56,539	302,265	283,637	$ 186,331
Texas Capital Bancshares, Inc.
Statement of Earnings
Interest on loans									3,402	3,401	3,398
Dividend income									10,400	10,400	10,400
Other income									96	151	142
Total income									13,898	13,952	13,940
Other non-interest income									3	17	7
Interest expense									10,515	12,342	12,031
Salaries and employee benefits									725	607	588
Legal and professional									3,238	3,093	2,020
Other non-interest expense									4,553	1,889	2,013
Total expense									19,031	17,931	16,652
Income (loss) before income taxes and equity in undistributed income of subsidiary									(5,130)	(3,962)	(2,705)
Income tax expense									(1,135)	(861)	(587)
Income before income taxes									(3,995)	(3,101)	(2,118)
Equity in undistributed income of subsidiary									68,100	312,932	293,321
Net income									64,105	309,831	291,203
Preferred stock dividends									9,750	9,750	9,750
Net income/(loss) available to common stockholders									$ 54,355	$ 300,081	$ 281,453

Parent Company Only (Details 2)

Parent Company Only (Details 2) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating activities
Net income	$ 60,176	$ 57,116	$ (34,316)	$ (16,687)	$ 64,420	$ 88,082	$ 77,812	$ 81,701	$ 66,289	$ 312,015	$ 293,387	$ 196,081
Adjustments to reconcile net income to net cash used in operating activities:
Increase in other assets									10,654	(143,617)	(123,542)
Increase (decrease) in other liabilities									5,749	98,735	2,411
Net cash provided by/(used in) operating activities									2,639,869	(240,268)	(679,715)
Investing Activities
Net cash used in investing activities									(2,935,317)	(2,276,077)	(1,992,746)
Financing Activities
Preferred dividends paid									(9,750)	(9,750)	(9,750)
Net cash provided by financing activities									5,076,245	3,861,863	2,846,935
Texas Capital Bancshares, Inc.
Operating activities
Net income									64,105	309,831	291,203
Adjustments to reconcile net income to net cash used in operating activities:
Equity in undistributed income of subsidiary									(68,100)	(312,932)	(293,321)
Amortization									101	101	101
Increase in other assets									(912)	(1,187)	(1,152)
Increase (decrease) in other liabilities									(448)	297	227
Net cash provided by/(used in) operating activities									(5,254)	(3,890)	(2,942)
Investing Activities
Net (increase)/decrease in loans held for investment									3,000	(3,000)	0
Investments in and advances to subsidiaries									0	0	(40,000)
Net cash used in investing activities									3,000	(3,000)	(40,000)
Financing Activities
Costs from issuance of stock related to stock-based awards and warrants									(1,986)	(1,459)	(2,382)
Preferred dividends paid									(9,750)	(9,750)	(9,750)
Net cash provided by financing activities									(11,736)	(11,209)	(12,132)
Net increase (decrease) in cash and cash equivalents									(13,990)	(18,099)	(55,074)
Cash and cash equivalents at beginning of period				$ 71,462				$ 89,561	71,462	89,561	144,635
Cash and cash equivalents at end of period	$ 57,472				$ 71,462				$ 57,472	$ 71,462	$ 89,561	$ 144,635

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Related Party Transactions [Abstract]
Deposits from related parties	$ 11.6	$ 13

Derivative Financial Instrume_3

Derivative Financial Instruments (Details 1) - Non-hedging - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Estimated fair value, asset derivative	$ 102,791	$ 48,866
Estimated fair value, liability derivative	99,326	51,492
Offsetting derivative liabilities	(71)	(182)
Offsetting derivative assets	(71)	(182)
Net asset derivatives included in the consolidated balance sheets	102,720	48,684
Net liability derivatives included in the consolidated balance sheets	99,255	51,310
Interest rate contract | Loan purchase commitments
Derivative [Line Items]
Notional amount	332,145	214,012
Estimated fair value, asset derivative	5,123	1,965
Estimated fair value, liability derivative	8	4
Interest rate contract | Loan purchase commitments
Derivative [Line Items]
Notional amount	485,326	2,654,653
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	2,675	4,587
Interest Rate Swap Future [Member]
Derivative [Line Items]
Notional Amount	320,000	0
Estimated fair value, asset derivative	474	0
Estimated fair value, liability derivative	0	0
Forward Sale Commitments [Member]
Derivative [Line Items]
Notional Amount	155,000	0
Estimated fair value, asset derivative	551	0
Estimated fair value, liability derivative	0	0
Financial institution counterparties | Commercial loan/lease | Interest rate swap
Derivative [Line Items]
Notional amount	1,922,956	1,548,234
Estimated fair value, asset derivative	71	182
Estimated fair value, liability derivative	96,246	46,518
Financial institution counterparties | Commercial loan/lease | Interest rate cap
Derivative [Line Items]
Notional amount	565,634	639,163
Estimated fair value, asset derivative	34	32
Estimated fair value, liability derivative	0	0
Financial institution counterparties | Commercial loan/lease | Foreign currency forward contracts
Derivative [Line Items]
Notional amount	6,667	2,219
Estimated fair value, asset derivative	214	169
Estimated fair value, liability derivative	78	0
Customer counterparties | Commercial loan/lease | Interest rate swap
Derivative [Line Items]
Notional amount	1,922,956	1,548,234
Estimated fair value, asset derivative	96,246	46,518
Estimated fair value, liability derivative	71	182
Customer counterparties | Commercial loan/lease | Interest rate cap
Derivative [Line Items]
Notional amount	565,634	639,163
Estimated fair value, asset derivative	0	0
Estimated fair value, liability derivative	34	32
Customer counterparties | Commercial loan/lease | Foreign currency forward contracts
Derivative [Line Items]
Notional amount	6,667	2,219
Estimated fair value, asset derivative	78	0
Estimated fair value, liability derivative	$ 214	$ 169

Derivative Financial Instrume_4

Derivative Financial Instruments Derivative Financial Instruments (Details 2) - Non-hedging - Commercial loan/lease - Interest rate swap	Dec. 31, 2020	Dec. 31, 2019
Interest rate received
Derivative [Line Items]
Weighted average fixed interest rate	3.14%	3.94%
Interest rate paid
Derivative [Line Items]
Weighted average fixed interest rate	1.38%	3.26%

Derivative Financial Instrume_5

Derivative Financial Instruments Derivative Financial Instruments (Details 3)	Dec. 31, 2020USD ($)instrument	Dec. 31, 2019USD ($)instrument
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 108,300,000	$ 56,600,000
Risk participation agreement - participant bank
Derivative [Line Items]
Instruments held | instrument	9	12
Maximum exposure	$ 6,000,000	$ 3,600,000
Notional amount	$ 119,500,000	$ 146,700,000
Risk participation agreement - lead bank
Derivative [Line Items]
Instruments held | instrument	16	12
Notional amount	$ 165,900,000	$ 145,900,000
Non-hedging | Commercial loan/lease
Derivative [Line Items]
Credit risk exposure, net of collateral pledged, relating to derivatives	$ 102,700,000	$ 48,700,000
Non-hedging | Interest rate cap | Commercial loan/lease
Derivative [Line Items]
Weighted average fixed interest rate	3.41%	3.29%
Interest-bearing deposits
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 104,400,000	$ 54,300,000
Other assets
Derivative [Line Items]
Cash collateral pledged for derivatives	$ 3,900,000	$ 2,300,000

Quarterly Financial Data (Detai

Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Selected Quarterly Financial Information [Abstract]
Interest income	$ 255,163	$ 243,731	$ 252,010	$ 306,008	$ 337,757	$ 355,101	$ 346,893	$ 325,561	$ 1,056,912	$ 1,365,312	$ 1,164,193
Interest expense	32,153	36,162	42,082	77,689	89,372	102,933	103,340	89,947	188,086	385,592	249,333
Net interest income	223,010	207,569	209,928	228,319	248,385	252,168	243,553	235,614	868,826	979,720	914,860
Provision for credit losses	32,000	30,000	100,000	96,000	17,000	11,000	27,000	20,000	258,000	75,000	87,000
Net interest income after provision for credit losses	191,010	177,569	109,928	132,319	231,385	241,168	216,553	215,614	610,826	904,720	827,860
Non-interest income	42,886	60,348	70,502	11,780	17,761	20,301	24,364	30,014	185,516	92,440	78,024
Non-interest expense	150,886	165,741	222,352	165,417	168,187	149,429	141,718	141,516	704,396	600,850	532,533	$ 466,858
Income/(loss) before income taxes	83,010	72,176	(41,922)	(21,318)	80,959	112,040	99,199	104,112	91,946	396,310	373,351	324,726
Income tax expense	22,834	15,060	(7,606)	(4,631)	16,539	23,958	21,387	22,411	25,657	84,295	79,964
Net income/(loss)	60,176	57,116	(34,316)	(16,687)	64,420	88,082	77,812	81,701	66,289	312,015	293,387	196,081
Preferred stock dividends	2,437	2,438	2,437	2,438	2,437	2,438	2,437	2,438	9,750	9,750	9,750
Net income/(loss) available to common stockholders	$ 57,739	$ 54,678	$ (36,753)	$ (19,125)	$ 61,983	$ 85,644	$ 75,375	$ 79,263	$ 56,539	$ 302,265	$ 283,637	$ 186,331
Basic earnings/(loss) per share:
Basic earnings per common share	$ 1.14	$ 1.08	$ (0.73)	$ (0.38)	$ 1.23	$ 1.70	$ 1.50	$ 1.58	$ 1.12	$ 6.01	$ 5.68
Diluted earnings/(loss) per share:
Diluted earnings per common share	$ 1.14	$ 1.08	$ (0.73)	$ (0.38)	$ 1.23	$ 1.70	$ 1.50	$ 1.58	$ 1.12	$ 5.99	$ 5.64
Average shares
Basic									50,430,326	50,286,300	49,936,702
Diluted									50,582,979	50,419,204	50,272,872