BancFirst (BANF) 10-Q 9 Aug 21 2021 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Jul. 30, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Trading Symbol	BANF
Entity Registrant Name	BancFirst Corporation
Entity Central Index Key	0000760498
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Title of 12(b) Security	Common Stock, $1.00 Par Value Per Share
Security Exchange Name	NASDAQ
Entity File Number	0-14384
Entity Incorporation, State or Country Code	OK
Entity Tax Identification Number	73-1221379
Entity Address, Address Line One	100 N. Broadway Ave.
Entity Address, City or Town	Oklahoma City
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	73102-8405
City Area Code	405
Local Phone Number	270-1086
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		32,784,513

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
ASSETS
Cash and due from banks	$ 268,299	$ 280,518
Interest-bearing deposits with banks	3,373,099	1,336,394
Debt securities held for investment (fair value: $2,990 and $2,984, respectively)	2,988	2,964
Debt securities available for sale at fair value	560,783	552,232
Loans held for sale	16,032	53,719
Loans held for investment (net of unearned interest)	6,191,230	6,394,506
Allowance for credit losses	(83,963)	(91,366)
Loans, net of allowance for credit losses	6,107,267	6,303,140
Premises and equipment, net	267,284	261,677
Other real estate owned	40,130	32,179
Intangible assets, net	19,283	18,999
Goodwill	149,922	149,922
Accrued interest receivable and other assets	210,200	220,613
Total assets	11,015,287	9,212,357
Deposits:
Noninterest-bearing	4,475,941	3,790,900
Interest-bearing	5,252,448	4,273,804
Total deposits	9,728,389	8,064,704
Short-term borrowings	3,100	1,100
Accrued interest payable and other liabilities	66,248	51,864
Subordinated debt	85,959	26,804
Total liabilities	9,883,696	8,144,472
Stockholders' equity:
Common stock, $1.00 par, 40,000,000 shares authorized; shares issued and outstanding: 32,784,513 and 32,719,852, respectively	32,785	32,720
Capital surplus	158,322	156,574
Retained earnings	935,067	871,161
Accumulated other comprehensive income, net of income tax of $1,705 and $2,513, respectively	5,417	7,430
Total stockholders' equity	1,131,591	1,067,885
Total liabilities and stockholders' equity	11,015,287	9,212,357
Senior Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value
Cumulative Preferred Stock [Member]
Stockholders' equity:
Preferred stock, value

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Securities, fair value	$ 2,990	$ 2,984
Common stock, par value	$ 1	$ 1
Common stock, shares authorized	40,000,000	40,000,000
Common stock, shares issued	32,784,513	32,719,852
Common stock, shares outstanding	32,784,513	32,719,852
Accumulated other comprehensive income, net of tax expense (benefit)	$ 1,705	$ 2,513
Senior Preferred Stock [Member]
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Cumulative Preferred Stock [Member]
Preferred stock, par value	$ 5	$ 5
Preferred stock, shares authorized	900,000	900,000
Preferred stock, shares issued	0	0

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
INTEREST INCOME
Loans, including fees	$ 82,447	$ 78,855	$ 160,109	$ 155,373
Securities:
Taxable	1,602	2,047	3,295	4,633
Tax-exempt	70	154	140	252
Interest-bearing deposits with banks	825	395	1,420	5,164
Total interest income	84,944	81,451	164,964	165,422
INTEREST EXPENSE
Deposits	2,003	3,750	4,325	13,150
Short-term borrowings		1	1	8
Subordinated debt	578	492	1,069	983
Total interest expense	2,581	4,243	5,395	14,141
Net interest income	82,363	77,208	159,569	151,281
(Benefit from) provision for credit losses	(9,949)	19,333	(9,949)	38,916
Net interest income after (benefit from)/provision for credit losses	92,312	57,875	169,518	112,365
NONINTEREST INCOME
Securities transactions (includes no accumulated other comprehensive income reclassifications)	172	(595)	267	(545)
Income from sales of loans	2,133	1,561	4,143	2,342
Insurance commissions	5,015	4,443	11,004	10,119
Cash management	3,068	4,255	6,071	8,575
Gain on sale of other assets	73	49	2,712	135
Other	10,369	2,241	14,366	4,014
Total noninterest income	44,618	32,082	84,553	67,227
NONINTEREST EXPENSE
Salaries and employee benefits	41,992	42,226	81,569	81,982
Occupancy, net	4,528	3,839	8,876	7,385
Depreciation	4,133	3,544	8,010	7,035
Amortization of intangible assets	809	968	1,602	1,932
Data processing services	1,660	1,629	3,338	3,321
Net loss/(income) from other real estate owned	3,357	(12)	4,867	(2,147)
Marketing and business promotion	1,648	1,485	3,527	3,840
Deposit insurance	766	365	1,642	501
Other	15,130	10,607	25,555	22,187
Total noninterest expense	74,023	64,651	138,986	126,036
Income before taxes	62,907	25,306	115,085	53,556
Income tax expense	14,715	4,576	24,373	10,218
Net income	$ 48,192	$ 20,730	$ 90,712	$ 43,338
NET INCOME PER COMMON SHARE
Basic	$ 1.47	$ 0.64	$ 2.77	$ 1.33
Diluted	$ 1.45	$ 0.63	$ 2.72	$ 1.31
OTHER COMPREHENSIVE (LOSS) GAIN
Unrealized (losses)/gains on debt securities, net of tax of $472, $85, $808 and $(2,091) respectively	$ (1,007)	$ (189)	$ (2,013)	$ 6,236
Comprehensive income	47,185	20,541	88,699	49,574
Trust Revenue [Member]
NONINTEREST INCOME
Revenue	3,264	3,368	6,366	7,023
Service Charges on Deposits [Member]
NONINTEREST INCOME
Revenue	$ 20,524	$ 16,760	$ 39,624	$ 35,564

Consolidated Statements of Co_2

Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Securities transactions accumulated other comprehensive income reclassifications	$ 0	$ 0	$ 0	$ 0
Unrealized (loss) gain on debt securities, tax	$ 472,000	$ 85,000	$ 808,000	$ (2,091,000)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	COMMON STOCK [Member]	CAPITAL SURPLUS [Member]	RETAINED EARNINGS [Member]	RETAINED EARNINGS [Member]CUMULATIVE EFFECT, PERIOD OF ADOPTION, ADJUSTMENT [Member]	ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) [Member]
Balance at beginning of period at Dec. 31, 2019		$ 32,694	$ 153,353	$ 815,488	$ 2,270	$ 3,454
Shares issued for stock options		28	507
Shares acquired and canceled		(59)		(3,039)
Net income	$ 43,338			$ 43,338
Accounting Standards Update Extensible List				us-gaap:AccountingStandardsUpdate201613Member
Dividends on common stock				$ (20,903)
Stock-based compensation arrangements			832
Net change						6,236
Balance at end of period at Jun. 30, 2020	1,034,199	32,663	154,692	837,154		9,690
Balance at beginning of period at Mar. 31, 2020		32,647	153,999	826,855		9,879
Shares issued for stock options		16	287
Net income	20,730			20,730
Dividends on common stock				(10,431)
Stock-based compensation arrangements			406
Net change						(189)
Balance at end of period at Jun. 30, 2020	1,034,199	32,663	154,692	837,154		9,690
Balance at beginning of period at Dec. 31, 2020	1,067,885	32,720	156,574	871,161		7,430
Shares issued for stock options		65	1,657
Net income	90,712			90,712
Dividends on common stock				(22,285)
Net cash settlement of options			(958)	(4,521)
Stock-based compensation arrangements			1,049
Net change						(2,013)
Balance at end of period at Jun. 30, 2021	1,131,591	32,785	158,322	935,067		5,417
Balance at beginning of period at Mar. 31, 2021		32,771	157,450	898,026		6,424
Shares issued for stock options		14	399
Net income	48,192			48,192
Dividends on common stock				(11,151)
Stock-based compensation arrangements			473
Net change						(1,007)
Balance at end of period at Jun. 30, 2021	$ 1,131,591	$ 32,785	$ 158,322	$ 935,067		$ 5,417

Consolidated Statements of St_2

Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Cumulative effect of change in accounting principle tax			$ 925
RETAINED EARNINGS [Member]
Dividend on common stock	$ 0.34	$ 0.32	$ 0.68	$ 0.64

Consolidated Statements of Cash

Consolidated Statements of Cash Flow (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 90,712	$ 43,338
Adjustments to reconcile to net cash provided by operating activities:
(Benefit from) provision for credit losses	(9,949)	38,916
Depreciation and amortization	9,612	8,967
Net amortization of securities premiums and discounts	1,670	(340)
Realized securities (gains)/losses	(267)	545
Gain on sales of loans	(4,143)	(2,342)
Cash receipts from the sale of loans originated for sale	221,051	171,433
Cash disbursements for loans originated for sale	(200,820)	(179,996)
Deferred income tax benefit	(1,495)	(3,987)
Gain on sale of other assets	(2,606)	(2,289)
Increase/(decrease) in interest receivable	2,048	(3,438)
Decrease in interest payable	(330)	(943)
Amortization of stock-based compensation arrangements	1,049	832
Excess tax benefit from stock-based compensation arrangements	(1,693)	(143)
Other, net	29,328	12,094
Net cash provided by operating activities	134,167	82,647
INVESTING ACTIVITIES
Net cash received from acquisitions, net of cash paid	12,412	18,397
Net cash paid from sale of assets and liabilities, net of cash received	(13,733)
Net decrease in federal funds sold	15,000	1,000
Purchases of held for investment debt securities	(845)	(1,395)
Purchases of available for sale debt securities	(251,673)	(255,178)
Proceeds from maturities, calls and paydowns of held for investment debt securities	820	470
Proceeds from maturities, calls and paydowns of available for sale debt securities	273,872	148,365
Purchase of equity securities	(470)	(234)
Proceeds from paydowns and sales of equity securities	392	437
Net change in loans	388,357	(993,997)
Purchases of premises, equipment and computer software	(15,200)	(30,292)
Purchase of tax credits	(2,048)	(357)
Other, net	3,567	5,641
Net cash provided by (used in) investing activities	410,451	(1,107,143)
FINANCING ACTIVITIES
Net change in deposits	1,444,742	958,030
Net change in short-term borrowings	2,000	7,000
Proceeds from long-term borrowings		3,000
Proceeds from issuance of subordinated notes, net of debt issuance costs	59,150
Issuance of common stock in connection with stock options, net	1,722	535
Common stock acquired		(3,098)
Net cash settlement of options	(5,479)
Cash dividends paid	(22,267)	(20,909)
Net cash provided by financing activities	1,479,868	944,558
Net increase/(decrease) in cash, due from banks and interest-bearing deposits	2,024,486	(79,938)
Cash, due from banks and interest-bearing deposits at the beginning of the period	1,616,912	1,868,281
Cash, due from banks and interest-bearing deposits at the end of the period	3,641,398	1,788,343
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid during the period for interest	5,736	15,053
Cash paid during the period for income taxes	15,400	5,075
Noncash investing and financing activities:
Cash consideration for acquisitions	21,000	2,861
Fair value of assets acquired in acquisitions	284,224	47,838
Liabilities assumed in acquisitions	256,412	45,040
Unpaid common stock dividends declared	$ 11,143	$ 10,447

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Description of Business and Summary of Significant Accounting Policies	(1) DESCRIPTION OF BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES The accounting and reporting policies of BancFirst Corporation and its subsidiaries (the “Company”) conform to accounting principles generally accepted in the United States of America (U.S. GAAP) and general practice within the banking industry. A summary of significant accounting policies can be found in Note (1) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. Basis of Presentation The accompanying unaudited interim consolidated financial statements include the accounts of BancFirst Corporation, Council Oak Partners, LLC, BancFirst Insurance Services, Inc., Pegasus Bank and BancFirst and its subsidiaries. The principal operating subsidiaries of BancFirst are Council Oak Investment Corporation, Council Oak Real Estate, Inc., BFTower, LLC, BFC-PNC LLC, and BancFirst Agency, Inc. All significant intercompany accounts and transactions have been eliminated. Assets held in a fiduciary or agency capacity are not assets of the Company and, accordingly, are not included in the unaudited interim consolidated financial statements. The accompanying unaudited interim consolidated financial statements and notes are presented in accordance with U.S. GAAP for interim financial information and the instructions for Form 10-Q adopted by the Securities and Exchange Commission (“SEC”). The information contained in the financial statements and footnotes included in BancFirst Corporation’s Annual Report on Form 10-K for the year ended December 31, 2020, should be referred to in connection with these unaudited interim consolidated financial statements. Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period. The unaudited interim consolidated financial statements contained herein reflect all adjustments, which are, in the opinion of management, necessary to provide a fair statement of the financial position and results of operations of the Company for the interim periods presented. All such adjustments are of a normal and recurring nature. Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with accounting principles generally accepted in the United States inherently involves the use of estimates and assumptions that affect the amounts reported in the financial statements and the related disclosures. These estimates relate principally to the determination of the allowance for credit losses, income taxes, the fair value of financial instruments and the valuation of intangibles. Such estimates and assumptions may change over time and actual amounts realized may differ from those reported.

Recent Developments, Including

Recent Developments, Including Mergers and Acquisitions	6 Months Ended
	Jun. 30, 2021
Recent Developments Including Mergers And Acquisitions [Abstract]
Recent Developments, Including Mergers and Acquisitions	(2) RECENT DEVELOPMENTS, INCLUDING MERGERS AND ACQUISITIONS On June 17, 2021, the Company completed a private placement, under Regulation D of the Securities Act of 1933, of $60 million aggregate principal amount of 3.50% Fixed-to-Floating Rate Subordinated Notes due 2036 (the “Subordinated Notes”) to various institutional accredited investors. See Note (7) of the Notes to Consolidated Financial Statements for a complete discussion of the Company’s subordinated debt. On May 20, 2021, the Company purchased approximately $284 million in total assets, which included $195 million in loans, and assumed approximately $256 million in deposits and certain other obligations, from The First National Bank and Trust Company of Vinita, Oklahoma for a purchase price of $21.0 million. The Company recorded a bargain purchase gain related to this purchase of approximately $6.0 million, which is included in other noninterest income on the statement of comprehensive income and other operating activities on the statement of cash flow. The bargain purchase gain is a noncash item on the statement of cash flow. In addition, the Company recorded expenses related to this purchase of approximately $4.0 million, which are included in noninterest expense. As a result of the purchase, the Company recorded a core deposit intangible of approximately $1.9 million. The effect of this purchase was included in the consolidated financial statement of the Company from the date of purchase forward. The purchase did not have a material effect on the Company’s consolidated financial statements. The First National Bank and Trust Company of Vinita was a nationally chartered bank with two banking locations in Vinita and Grove, Oklahoma. The preliminary purchase price assessment remains an ongoing process and is subject to change for up to one year subsequent to the closing date. On January 22, 2021, the Company sold approximately $21 million in loans and approximately $38 million in deposits from its Hugo, Oklahoma branch to AmeriState Bank in Atoka, Oklahoma. The Company recorded a gain on the transaction of $2.5 million, which is included in noninterest income.

Securities

Securities	6 Months Ended
	Jun. 30, 2021
Investments Debt And Equity Securities [Abstract]
Securities	( 3 ) SECURITIES The following table summarizes the amortized cost and estimated fair values of debt securities held for investment: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value June 30, 2021 (Dollars in thousands) Mortgage backed securities (1) $ 43 $ 2 $ — $ 45 States and political subdivisions 2,445 — — 2,445 Other securities 500 — — 500 Total $ 2,988 $ 2 $ — $ 2,990 December 31, 2020 Mortgage backed securities (1) $ 59 $ 3 $ — $ 62 States and political subdivisions 2,405 18 (1 ) 2,422 Other securities 500 — — 500 Total $ 2,964 $ 21 $ (1 ) $ 2,984 The following table summarizes the amortized cost and estimated fair values of debt securities available for sale: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value June 30, 2021 (Dollars in thousands) U.S. treasuries $ 465,762 $ 6,680 $ (600 ) $ 471,842 U.S. federal agencies 25,273 324 (2 ) 25,595 Mortgage backed securities (1) 38,407 471 (109 ) 38,769 States and political subdivisions 10,874 227 — 11,101 Asset backed securities 13,346 130 — 13,476 Total $ 553,662 $ 7,832 $ (711 ) $ 560,783 December 31, 2020 U.S. treasuries $ 465,416 $ 9,820 $ — $ 475,236 U.S. federal agencies 19,697 1 (60 ) 19,638 Mortgage backed securities (1) 15,268 428 — 15,696 States and political subdivisions 28,571 377 — 28,948 Asset backed securities 13,337 — (623 ) 12,714 Total $ 542,289 $ 10,626 $ (683 ) $ 552,232 (1) Primarily consists of FHLMC, FNMA, GNMA and mortgage backed securities through U.S. agencies. The maturities of debt securities held for investment and available for sale are summarized in the following table using contractual maturities. Actual maturities may differ from contractual maturities due to obligations that are called or prepaid. For purposes of the maturity table, mortgage-backed securities, which are not due at a single maturity date, have been presented at their contractual maturity. June 30, 2021 December 31, 2020 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value (Dollars in thousands) Held for Investment Contractual maturity of debt securities: Within one year $ 576 $ 576 $ 807 $ 809 After one year but within five years 2,407 2,409 2,091 2,110 After five years but within ten years 4 4 65 64 After ten years 1 1 1 1 Total $ 2,988 $ 2,990 $ 2,964 $ 2,984 Available for Sale Contractual maturity of debt securities: Within one year $ 110,293 $ 111,495 $ 339,752 $ 341,102 After one year but within five years 373,494 378,554 162,401 171,135 After five years but within ten years 9,925 10,467 3,753 3,910 After ten years 59,950 60,267 36,383 36,085 Total debt securities $ 553,662 $ 560,783 $ 542,289 $ 552,232 The following table is a summary of the Company’s book value of securities that were pledged as collateral for public funds on deposit, repurchase agreements and for other purposes as required or permitted by law: June 30, 2021 December 31, 2020 (Dollars Book value of pledged securities $ 498,877 $ 490,833

Loans Held for Investment and A

Loans Held for Investment and Allowance for Credit Losses on Loans	6 Months Ended
	Jun. 30, 2021
Receivables [Abstract]
Loans Held for Investment and Allowance for Credit Losses on Loans	( 4 ) LOANS HELD FOR INVESTMENT AND ALLOWANCE FOR CREDIT LOSSES ON LOANS Loans held for investment are summarized by portfolio segment as follows: June 30, 2021 December 31, 2020 Amount Amount (Dollars in thousands) BancFirst Real estate: Commercial real estate owner occupied $ 661,530 $ 641,987 Commercial real estate non-owner occupied 989,560 971,158 Construction and development < 60 months 297,205 229,615 Construction residential real estate < 60 months 208,210 206,195 Residential real estate first lien 865,557 853,316 Residential real estate all other 163,290 168,081 Farmland 269,008 252,958 Commercial and agricultural non-real estate 1,105,777 1,159,810 Consumer non-real estate 371,557 355,405 Oil and gas 130,459 179,355 Other loans (2) 543,034 822,078 Pegasus Bank 586,043 554,548 Total (1) $ 6,191,230 $ 6,394,506 (1) Excludes accrued interest receivable of $22.9 million at June 30, 2021 and $26.0 million at December 31, 2020, that is recorded in accrued interest receivable and other assets. (2) Includes PPP loans held for investment of $368.6 million, net of unamortized processing fees of $16.6 million at June 30, 2021 and $652.7 million, net of unamortized processing fees of $14.5 million at December 31, 2020. Other loans. Other loans consist of loans approved by the Small Business Administration (“SBA”), which include loans funded through the Paycheck Protection Program (“PPP”). Since PPP loans are fully guaranteed by the SBA, there is no expected credit loss related to these loans. In April 2020, the Company began originating loans to qualified small businesses under the PPP administered by the SBA. T he Company had processing fees, which were recognized as interest income related to the PPP loans totaling $11.9 million and $3.7 million during the three months ended June 30, 2021 and 2020, respectively and $21.7 million and $3.7 million during the six months ended June 30, 2021 and 2020, respectively. BancFirst’s loans are mostly to customers within Oklahoma and approximately 56% of the loans are secured by real estate. Credit risk on loans is managed through limits on amounts loaned to individual and related borrowers, underwriting standards and loan monitoring procedures. The amounts and types of collateral obtained, if any, to secure loans are based upon the Company’s underwriting standards and management’s credit evaluation. Collateral varies, but may include real estate, equipment, accounts receivable, inventory, livestock and securities. The Company’s interest in collateral is secured through filing mortgages and liens, and in some cases, by possession of the collateral. Pegasus Bank’s loans are mostly to customers within Texas and approximately $297 million or 51% of the loans are secured by real estate at June 30, 2021. Pegasus Bank’s commercial and agricultural non-real estate loans were approximately $268 million at June 30, 2021 and approximately $262 million at December 31, 2020. BancFirst and Pegasus Bank’s commercial and agricultural non-real estate and oil and gas loan categories include upstream and midstream energy loans, and loans to companies that provide ancillary services to the energy industry, such as transportation, wellsite preparation contractors and equipment manufacturers. Energy loans are summarized as follows: June 30, 2021 December 31, 2020 Amount Amount (Dollars in thousands) BancFirst energy loans Upstream $ 141,651 $ 190,788 Midstream 37,134 49,734 Ancillary services 74,919 59,410 Pegasus Bank energy loans Upstream 127,736 107,103 Midstream 8,797 11,047 Ancillary services 14,049 12,503 Total $ 404,286 $ 430,585 Accounting policies related to appraisals, and charge-offs are disclosed in Note (1) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. Troubled Debt Restructurings, Other Real Estate Owned and Repossessed Assets and Held for Sale Assets The following is a summary of troubled debt restructurings and other real estate owned and repossessed assets: June 30, December 31, 2021 2020 (Dollars in thousands) Troubled debt restructurings $ 7,485 $ 7,784 Other real estate owned and repossessed assets $ 40,183 $ 32,480 The Company charges interest on principal balances outstanding on troubled debt restructurings during deferral periods. The current and future financial effects of the recorded balance of loans considered to be troubled debt restructurings were not considered to be material. During the first half of 2021, the Company completed the move to its new corporate headquarters and transferred approximately $2.4 million from premises and equipment to other real estate owned related to its previous headquarters. In addition, other real estate owned of approximately $2.5 million was purchased from the First National Bank and Trust Company of Vinita, Oklahoma. During the first half of 2021, the Company sold property held in other real estate owned for a total loss of $105,000, compared to a total gain of $2.3 million in the first half of 2020. Nonaccrual loans Had nonaccrual loans performed in accordance with their original contractual terms, the Company would have recognized additional interest income of approximately $1.2 million for the six months ended June 30, 2021 and approximately $983,000 for the six months ended June 30, 2020. Nonaccrual loans guaranteed by government agencies totaled approximately $3.5 million at June 30, 2021 and approximately $7.8 million at December 31, 2020. The following table is a summary of amounts included in nonaccrual loans, segregated by portfolio segment. June 30, 2021 December 31, 2020 (Dollars in thousands) BancFirst Real estate: Commercial real estate owner occupied $ 2,572 $ 1,404 Commercial real estate non-owner occupied 422 4,719 Construction and development < 60 months 88 95 Construction residential real estate < 60 months — — Residential real estate first lien 3,518 3,615 Residential real estate all other 1,188 1,362 Farmland 6,354 7,901 Commercial and agricultural non-real estate 13,185 12,782 Consumer non-real estate 188 268 Oil and gas — — Other loans 2,287 5,399 Pegasus Bank — — Total $ 29,802 $ 37,545 Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due. The following table presents an age analysis of our loans held for investment: Age Analysis of Past Due Loans 30-59 Days Past Due 60-89 Days Past Due 90 Days and Greater Total Past Due Loans Current Loans Total Loans Accruing Loans 90 Days or More Past Due (Dollars in thousands) As of June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 604 $ — $ 1,012 $ 1,616 $ 659,914 $ 661,530 $ 80 Commercial real estate non-owner occupied 205 — 112 317 989,243 989,560 37 Construction and development < 60 months 53 1,605 137 1,795 295,410 297,205 137 Construction residential real estate < 60 months 103 — — 103 208,107 208,210 — Residential real estate first lien 3,639 447 3,989 8,075 857,482 865,557 2,070 Residential real estate all other 1,195 40 1,536 2,771 160,519 163,290 458 Farmland 1,036 989 4,327 6,352 262,656 269,008 157 Commercial and agricultural non-real estate 3,780 2,821 8,393 14,994 1,090,783 1,105,777 638 Consumer non-real estate 1,620 353 221 2,194 369,363 371,557 190 Oil and gas — — — — 130,459 130,459 — Other loans 1,472 478 2,102 4,052 538,982 543,034 619 Pegasus Bank — — — — 586,043 586,043 — Total $ 13,707 $ 6,733 $ 21,829 $ 42,269 $ 6,148,961 $ 6,191,230 $ 4,386 As of December 31, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 1,096 $ 108 $ 1,164 $ 2,368 $ 639,619 $ 641,987 $ — Commercial real estate non-owner occupied 323 — 34 357 970,801 971,158 35 Construction and development < 60 months 511 86 — 597 229,018 229,615 — Construction residential real estate < 60 months 1,106 — 282 1,388 204,807 206,195 282 Residential real estate first lien 5,428 1,463 2,978 9,869 843,447 853,316 945 Residential real estate all other 520 55 1,606 2,181 165,900 168,081 384 Farmland 1,297 344 6,223 7,864 245,094 252,958 135 Commercial and agricultural non-real estate 2,788 1,794 4,345 8,927 1,150,883 1,159,810 465 Consumer non-real estate 2,154 501 534 3,189 352,216 355,405 386 Oil and gas — — — — 179,355 179,355 — Other loans 951 1,223 6,618 8,792 813,286 822,078 2,170 Pegasus Bank — — — — 554,548 554,548 — Total $ 16,174 $ 5,574 $ 23,784 $ 45,532 $ 6,348,974 $ 6,394,506 $ 4,802 Due to the impacts of the COVID-19 pandemic, the Company had approximately $61.8 million in modified loans as of June 30, 2021 and $81.7 million in modified loans as of December 31, 2020, most of which were secured by commercial real estate. These modifications were undertaken in response to Section 4013 of the CARES Act and the regulatory intent outlined in the Interagency Statement on Loan Modifications by Financial Institutions Working with Customers Affected by the Coronavirus and to provide businesses financial flexibility until the economy has time to recover to a more normal level of activity. However, these modifications, which typically involve payment modifications and forbearance, also have the effect of delaying recognition of loans that may ultimately be permanently impaired. The timing and extent of such consequences are difficult to ascertain at this time and are dependent on the duration of the COVID-19 pandemic, the level and success of the government’s economic stimulus, and further regulatory guidance. These modified loans are included in Current Loans in the table above. Credit Quality Indicators The Company considers credit quality indicators to monitor the credit risk in the loan portfolio including volume and severity of loan delinquencies, nonaccrual loans, internal grading of loans, historical credit loss experience and economic conditions. An internal risk grading system is used to indicate the credit risk of loans. The loan grades used by the Company are for internal risk identification purposes and do not directly correlate to regulatory classification categories or any financial reporting definitions. The general characteristics of the risk grades and the table summarizing our gross loans held for investment by year of origination and internally assigned credit grades as of December 31, 2020, are disclosed in Note (5) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. The Company’s revolving loans that are converted to term loans are not material and therefore have not been presented. The following table summarizes our gross loans held for investment by year of origination and internally assigned credit grades as of June 30, 2021: Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Amortized Cost Basis Total (Dollars in thousands) As of June 30, 2021 BancFirst Commercial real estate owner occupied Grade 1 $66,327 $135,671 $83,146 $53,559 $36,961 $112,760 $11,507 $499,931 Grade 2 17,354 38,028 30,351 10,695 9,710 40,707 4,904 151,749 Grade 3 3 3,905 27 266 476 2,621 — 7,298 Grade 4 349 — 921 539 — 436 307 2,552 Total commercial real estate owner occupied loans 84,033 177,604 114,445 65,059 47,147 156,524 16,718 661,530 Commercial real estate non-owner occupied Grade 1 95,260 227,302 147,192 62,169 61,402 137,491 18,024 748,840 Grade 2 16,345 59,541 44,838 37,862 19,357 43,884 4,657 226,484 Grade 3 7,453 — 3,412 214 1,607 865 — 13,551 Grade 4 — — 50 37 — 598 — 685 Total commercial real estate non-owner occupied loans 119,058 286,843 195,492 100,282 82,366 182,838 22,681 989,560 Construction and development < 60 months Grade 1 91,143 63,018 66,976 11,381 2,547 3,210 10,454 248,729 Grade 2 12,579 12,938 12,391 2,187 1,811 773 2,128 44,807 Grade 3 1,753 1,690 130 7 — — — 3,580 Grade 4 — — 61 8 20 — — 89 Total construction and development < 60 months 105,475 77,646 79,558 13,583 4,378 3,983 12,582 297,205 Construction residential real estate < 60 months Grade 1 101,482 69,169 52 — 20 30 7,264 178,017 Grade 2 14,182 14,919 — 109 — 437 — 29,647 Grade 3 546 — — — — — — 546 Total construction residential real estate < 60 months 116,210 84,088 52 109 20 467 7,264 208,210 Residential real estate first lien Grade 1 134,782 188,553 109,336 69,907 54,107 154,974 — 711,659 Grade 2 22,669 25,098 16,385 19,237 10,187 42,381 — 135,957 Grade 3 1,102 1,809 2,526 901 1,360 4,832 — 12,530 Grade 4 49 511 442 1,149 934 2,326 — 5,411 Total residential real estate first lien 158,602 215,971 128,689 91,194 66,588 204,513 — 865,557 Residential real estate all other Grade 1 9,847 16,428 11,139 8,009 5,157 15,276 28,321 94,177 Grade 2 746 3,263 1,743 1,325 1,137 2,367 53,510 64,091 Grade 3 272 140 410 248 718 376 1,042 3,206 Grade 4 14 211 — 579 15 652 345 1,816 Total residential real estate all other 10,879 20,042 13,292 10,161 7,027 18,671 83,218 163,290 Farmland Grade 1 26,621 46,638 25,418 18,375 13,983 35,431 7,521 173,987 Grade 2 8,767 9,048 26,148 5,702 5,457 13,424 10,709 79,255 Grade 3 2,786 2,068 1,676 300 742 1,213 1,842 10,627 Grade 4 — 1,195 — 3,187 296 183 278 5,139 Total farmland 38,174 58,949 53,242 27,564 20,478 50,251 20,350 269,008 Commercial and agricultural non-real estate Grade 1 190,653 135,726 105,770 64,491 54,567 54,870 220,348 826,425 Grade 2 38,938 47,478 29,481 11,780 3,885 18,985 68,353 218,900 Grade 3 4,900 5,500 1,706 12,010 1,858 639 21,708 48,321 Grade 4 262 1,783 1,555 599 811 1,299 5,822 12,131 Total commercial and agricultural non-real estate 234,753 190,487 138,512 88,880 61,121 75,793 316,231 1,105,777 Consumer non-real estate Grade 1 110,171 116,215 64,985 27,641 9,497 4,018 7,084 339,611 Grade 2 9,362 9,659 4,641 2,833 1,099 1,653 287 29,534 Grade 3 229 405 787 290 154 147 3 2,015 Grade 4 14 67 180 58 19 55 4 397 Total consumer non-real estate 119,776 126,346 70,593 30,822 10,769 5,873 7,378 371,557 Oil and gas Grade 1 53,326 115 59 66 — 3,444 33,676 90,686 Grade 2 10,051 3,347 69 — — — 9,419 22,886 Grade 3 16,887 — — — — — — 16,887 Total oil and gas 80,264 3,462 128 66 — 3,444 43,095 130,459 Other loans Grade 1 379,715 34,608 29,464 24,034 18,060 25,568 23,298 534,747 Grade 2 — — 250 17 2,638 2,434 820 6,159 Grade 3 — 11 225 10 1 99 199 545 Grade 4 — 137 — — 294 140 1,012 1,583 Total other loans 379,715 34,756 29,939 24,061 20,993 28,241 25,329 543,034 Pegasus Bank Grade 1 64,138 87,556 58,223 7,261 16,202 52,432 153,260 439,072 Grade 2 27,016 14,313 18,116 10,578 21,378 6,717 48,741 146,859 Grade 3 — 112 — — — — — 112 Total Pegasus Bank 91,154 101,981 76,339 17,839 37,580 59,149 202,001 586,043 Total loans held for investment $1,538,093 $1,378,175 $900,281 $469,620 $358,467 $789,747 $756,847 $6,191,230 Allowance for Credit Losses Methodology On January 1, 2020, the Company adopted ASC 326, which replaces the incurred loss methodology for determining its 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 decreased by $3.2 million, with no impact to the consolidated statement of income. The allowance for credit losses is measured on a collective (pool) basis when similar risk characteristics exist by identifying by portfolio segments, the applicable weighted average life and measuring the allowance for credit losses using the vintage loss analysis adjusted for qualitative factors. The weighted average lives of the Company’s loans segments are disclosed in Note (1) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. The decrease in the allowance for credit loss during the second quarter of 2021 was primarily driven by a reversal of provision during the quarter based on sustained improvements in the economy, both nationally and in Oklahoma, which reduced the amount of expected credit loss within the loan portfolio. This reduction was partially offset by additional allowance for credit loss required by newly acquired loans purchased with credit deterioration. The following table details activity in the allowance for credit losses on loans for the period presented. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. Allowance for Credit Losses Balance at beginning of period Initial allowance on loans purchased with credit deterioration Charge- offs Recoveries Net charge-offs (Benefit from) /Provision for credit losses on loans Balance at end of period (Dollars in thousands) Three Months Ended June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 6,595 $ 987 $ — $ 1 $ 1 $ (828 ) $ 6,755 Commercial real estate non-owner occupied 16,955 633 (758 ) — (758 ) (2,340 ) 14,490 Construction and development < 60 months 2,743 173 — 2 2 (25 ) 2,893 Construction residential real estate < 60 months 983 — — — — (94 ) 889 Residential real estate first lien 2,592 117 (9 ) 12 3 93 2,805 Residential real estate all other 1,873 — (30 ) 1 (29 ) 97 1,941 Farmland 3,077 643 — 1 1 (6 ) 3,715 Commercial and agricultural non-real estate 32,685 4,711 (3,433 ) 125 (3,308 ) (2,473 ) 31,615 Consumer non-real estate 3,256 8 (209 ) 86 (123 ) 174 3,315 Oil and gas 12,131 — — — — (4,314 ) 7,817 Other loans 3,190 — (9 ) — (9 ) (43 ) 3,138 Pegasus Bank 4,780 — — — — (190 ) 4,590 Total $ 90,860 $ 7,272 $ (4,448 ) $ 228 $ (4,220 ) $ (9,949 ) $ 83,963 Six Months Ended June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 7,035 $ 987 $ — $ 1 $ 1 $ (1,268 ) $ 6,755 Commercial real estate non-owner occupied 11,842 633 (796 ) — (796 ) 2,811 14,490 Construction and development < 60 months 2,560 173 — 5 5 155 2,893 Construction residential real estate < 60 months 627 — — — — 262 889 Residential real estate first lien 2,570 117 (52 ) 27 (25 ) 143 2,805 Residential real estate all other 2,230 — (46 ) 4 (42 ) (247 ) 1,941 Farmland 3,136 643 — 1 1 (65 ) 3,715 Commercial and agricultural non-real estate 32,400 4,711 (3,537 ) 151 (3,386 ) (2,110 ) 31,615 Consumer non-real estate 3,377 8 (622 ) 198 (424 ) 354 3,315 Oil and gas 17,851 — — — — (10,034 ) 7,817 Other loans 3,182 — (61 ) — (61 ) 17 3,138 Pegasus Bank 4,556 — — 1 1 33 4,590 Total $ 91,366 $ 7,272 $ (5,114 ) $ 388 $ (4,726 ) $ (9,949 ) $ 83,963 Allowance for Credit Losses Balance at beginning of period Impact of CECL adoption Initial allowance on loans purchased with credit deterioration Charge- offs Recoveries Net charge-offs Provision for /(benefit from) credit losses on loans Balance at end of period (Dollars in thousands) Three Months Ended June 30, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 4,544 $ — $ — $ (113 ) $ 1 $ (112 ) $ 2,198 $ 6,630 Commercial real estate non-owner occupied 5,935 — — — — — 3,548 9,483 Construction and development < 60 months 1,136 — — (56 ) 3 (53 ) 672 1,755 Construction residential real estate < 60 months 1,618 — — (28 ) — (28 ) 669 2,259 Residential real estate first lien 6,192 — — (66 ) 4 (62 ) 2,423 8,553 Residential real estate all other 2,292 — — (7 ) 1 (6 ) 434 2,720 Farmland 1,788 — — — — — 723 2,511 Commercial and agricultural non-real estate 33,993 — — (287 ) 66 (221 ) 264 34,036 Consumer non-real estate 3,385 — — (235 ) 57 (178 ) 1,507 4,714 Oil and gas 3,283 — — — — — 7,186 10,469 Other loans 2,751 — — — — — (238 ) 2,513 Pegasus Bank 3,163 — — 330 417 747 (53 ) 3,857 Total $ 70,080 $ — $ — $ (462 ) $ 549 $ 87 $ 19,333 $ 89,500 Six Months Ended June 30, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 5,625 $ (2,806 ) $ 432 $ (113 ) $ 1 $ (112 ) $ 3,491 $ 6,630 Commercial real estate non-owner occupied 8,358 (5,507 ) — — — — 6,632 9,483 Construction and development < 60 months 2,214 (1,056 ) — (59 ) 3 (56 ) 653 1,755 Construction residential real estate < 60 months 1,933 (778 ) — (29 ) — (29 ) 1,133 2,259 Residential real estate first lien 8,692 (3,831 ) 7 (218 ) 6 (212 ) 3,897 8,553 Residential real estate all other 2,767 (1,408 ) — (32 ) 28 (4 ) 1,365 2,720 Farmland 2,821 (1,408 ) 1 — — — 1,097 2,511 Commercial and agricultural non-real estate 13,462 13,195 62 (374 ) 83 (291 ) 7,608 34,036 Consumer non-real estate 3,252 (622 ) — (556 ) 114 (442 ) 2,526 4,714 Oil and gas 1,883 (1,346 ) — — — — 9,932 10,469 Other loans 2,632 (116 ) — — 2 2 (5 ) 2,513 Pegasus Bank 599 2,488 — (241 ) 424 183 587 3,857 Total $ 54,238 $ (3,195 ) $ 502 $ (1,622 ) $ 661 $ (961 ) $ 38,916 $ 89,500 Purchased Credit Deteriorated Loans The Company has previously purchased loans, for which there was, at acquisition, evidence of more than insignificant deterioration of credit quality since origination. The credit-deteriorated loans purchased during the six-month periods ended June 30, 2021 and June 30, 2020 were as follows: Loans acquired with deteriorated credit quality (Dollars in thousands) For the period ended June 30, 2021 Purchase price of loans at acquisition $ 26,779 Allowance for credit losses at acquisition 7,272 Par value of acquired loans at acquisition $ 34,051 For the period ended June 30, 2020 Purchase price of loans at acquisition $ 1,761 Allowance for credit losses at acquisition 502 Par value of acquired loans at acquisition $ 2,263 Collateral Dependent Loans 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. During the six months ended June 30, 2021 and 2020, no material amount of interest income was recognized on collateral-dependent loans subsequent to their classification as collateral-dependent. The following table summarizes collateral-dependent gross loans held for investment by collateral type and the related specific allocation as follows: Collateral Type Real Estate Business Assets Energy Reserves Other Assets Total Specific Allocation (Dollars in thousands) As of June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 645 $ — $ — $ — $ 645 $ 176 Commercial real estate non-owner occupied — — — — — — Construction and development < 60 months — — — — — — Construction residential real estate < 60 months — — — — — — Residential real estate first lien 806 — — — 806 158 Residential real estate all other 650 — — — 650 568 Farmland 3,215 — — — 3,215 1,123 Commercial and agricultural non-real estate — 5,211 — 5,188 10,399 778 Consumer non-real estate — — — 22 22 4 Oil and gas — — — — — — Other loans — 15 — — 15 15 Pegasus Bank — — — — — — Total collateral-dependent loans held for investment $ 5,316 $ 5,226 $ — $ 5,210 $ 15,752 $ 2,822 Collateral Type Real Estate Business Assets Energy Reserves Other Assets Total Specific Allocation (Dollars in thousands) As of December 31, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 848 $ — $ — $ — $ 848 $ 226 Commercial real estate non-owner occupied 4,719 — — — 4,719 1,000 Construction and development < 60 months — — — — — — Construction residential real estate < 60 months — — — — — — Residential real estate first lien 860 — — — 860 151 Residential real estate all other 866 — — — 866 616 Farmland 3,258 — — — 3,258 1,114 Commercial and agricultural non-real estate — 8,460 — 413 8,873 2,813 Consumer non-real estate — — — 109 109 58 Oil and gas — — — — — — Other loans — 13 — — 13 12 Pegasus Bank 1,257 — — — 1,257 222 Total collateral-dependent loans held for investment $ 11,808 $ 8,473 $ — $ 522 $ 20,803 $ 6,212 Non-Cash Transfers from Loans and Premises and Equipment Transfers from loans and premises and equipment to other real estate owned and repossessed assets are non-cash transactions, and are not included in the statements of cash flow. Transfers from loans and premises and equipment to other real estate owned and repossessed assets during the periods presented are summarized as follows: Six Months Ended June 30, 2021 2020 (Dollars in thousands) Other real estate owned $ 9,438 $ 2,876 Repossessed assets 427 722 Total $ 9,865 $ 3,598

Intangible Assets and Goodwill

Intangible Assets and Goodwill	6 Months Ended
	Jun. 30, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets and Goodwill	( 5 ) INTANGIBLE ASSETS AND GOODWILL The following is a summary of intangible assets: Gross Carrying Amount Accumulated Amortization Net Carrying Amount (Dollars in thousands) As of June 30, 2021 Core deposit intangibles $ 30,849 $ (12,120 ) $ 18,729 Customer relationship intangibles 3,350 (2,796 ) 554 Total $ 34,199 $ (14,916 ) $ 19,283 As of December 31, 2020 Core deposit intangibles $ 33,411 $ (15,076 ) $ 18,335 Customer relationship intangibles 3,350 (2,686 ) 664 Total $ 36,761 $ (17,762 ) $ 18,999 The following is a summary of goodwill by business segment: Other Executive, Metropolitan Community Pegasus Financial Operations Banks Banks Bank Services & Support Consolidated (Dollars in thousands) Six months ended June 30, 2021 Balance at beginning and end of period $ 13,767 $ 61,212 $ 68,855 $ 5,464 $ 624 $ 149,922 Additional information for intangible assets can be found in Note (7) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020.

Leases

Leases	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Leases	(6) LEASES Lessee The Company has operating leases, which primarily consist of office space in buildings, ATM locations, storage facilities, parking lots, equipment and land on which it owns certain buildings. Rent expense for all operating leases, including those rented on a monthly or temporary basis, totaled approximately $462,000 and approximately $453,000 for the three months ended June 30, 2021 and June 30, 2020, respectively. Rent expense for all operating leases, including those rented on a monthly or temporary basis, totaled approximately $966,000 and $916,000 for the six months ended June 30, 2021 and June 30, 2020, respectively. As of June 30, 2021, right of use lease asset included in accrued interest receivable and other assets on the balance sheet totaled $3.8 million, and a related lease liability included in accrued interest payable and other liabilities on the balance sheet totaled $3.7 million. There have been no significant changes in our expected future minimum lease payments since December 31, 2020. The future minimum lease payments are disclosed in Note (20) to the Company’s Annual Report on Form 10-K for the year ended December 31, 2020. As of June 30, 2021, our operating leases have a weighted-average remaining lease term of 3.3 years and a weighted-average discount rate of 2.8 percent. The following table presents minimum future commitments by year for the Company’s operating leases. Such commitments are reflected as undiscounted values and are reconciled to the discounted present value recognized on the balance sheet. June 30, 2021 (Dollars in thousands) 2021 (six months) $ 703 2022 1,212 2023 708 2024 345 2025 286 Thereafter 893 Total lease payments 4,147 Less imputed Interest (497 ) Operating lease liability $ 3,650 Lessor The Company is a lessor of operating leases, which primarily consist of office space in buildings and parking lots. These assets are classified on the balance sheet as premises and equipment. The Company had operating lease revenue of $1.3 million and $1.4 million for the three months ended June 30, 2021 and June 30, 2020, respectively. The Company had operating lease revenue of $2.7 million and $2.8 million for the six months ended June 30, 2021 and June 30, 2020, respectively. Lease revenue is included in occupancy, net on the consolidated statement of comprehensive income. The Company does not have operating leases that extend beyond 2031. The following table presents the scheduled minimum future contractual rent to be received under the remaining non-cancelable term of the operating leases: June 30, 2021 (Dollars in thousands) 2021 (six months) $ 1,765 2022 2,857 2023 2,636 2024 2,571 2025 1,946 2026-2031 6,146 Total future minimum lease payments $ 17,921

Subordinated Debt

Subordinated Debt	6 Months Ended
	Jun. 30, 2021
Brokers And Dealers [Abstract]
Subordinated Debt	(7) SUBORDINATED DEBT In January 2004, the Company established BFC Capital Trust II (“BFC II”), a trust formed under the Delaware Business Trust Act. The Company owns all of the common securities of BFC II. In February 2004, BFC II issued $25 million of aggregate liquidation amount of 7.20% Cumulative Trust Preferred Securities (the “Cumulative Trust Preferred Securities”) to other investors. In March 2004, BFC II issued an additional $1 million in Cumulative Trust Preferred Securities through the execution of an over-allotment option. The proceeds from the sale of the Cumulative Trust Preferred Securities and the common securities of BFC II were invested in $26.8 million of 7.20% Junior Subordinated Debentures of the Company. Interest payments on the $26.8 million of 7.20% Junior Subordinated Debentures are payable January 15, April 15, July 15 and October 15 of each year. Such interest payments may be deferred for up to twenty consecutive quarters. The stated maturity date of the $26.8 million of 7.20% Junior Subordinated Debentures is March 31, 2034, but they are subject to mandatory redemption pursuant to optional prepayment terms. The Cumulative Trust Preferred Securities represent an undivided interest in the $26.8 million of 7.20% Junior Subordinated Debentures and are guaranteed by the Company. During any deferral period or during any event of default, the Company may not declare or pay any dividends on any of its capital stock. The Cumulative Trust Preferred Securities were callable at par, in whole or in part, after March 31, 2009. On June 17, 2021, the Company completed a private placement, under Regulation D of the Securities Act of 1933, of $60 million aggregate principal amount of 3.50% Fixed-to-Floating Rate Subordinated Notes due 2036 (the “Subordinated Notes”) to various institutional accredited investors. The sale of the Subordinated Notes was pursuant to a Subordinated Note Purchase Agreement entered into with each of the investors. The Subordinated Notes have been structured to qualify as Tier 2 capital under bank regulatory guidelines. The net proceeds to the Company from the sale of the Subordinated Notes was approximately $59.15 million after deducting commissions and offering expenses of $850,000. The Company expects to use the proceeds from the sale of the Subordinated Notes for general corporate purposes. The Subordinated Notes will initially bear interest at a fixed rate of 3.50% per annum, from and including June 17, 2021 to but excluding June 30, 2031, payable semi-annually in arrears on June 30 and December 31 of each year, commencing December 31, 2021. Then, from and including June 30, 2031, to but excluding the maturity date, the Subordinated Notes will bear interest at a floating rate equal to the benchmark (initially, three-month term SOFR), reset quarterly, plus a spread of 229 basis points, payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year. The Subordinated Notes mature on June 30, 2036. The Company may, at its option, beginning with the interest payment date of June 30, 2031, and on any scheduled interest payment date thereafter, redeem the Subordinated Notes, in whole or in part. In addition, the Company may redeem all, but not less than all, of the Subordinated Notes at any time upon the occurrence of a “Tier 2 Capital Event,” a “Tax Event” or an “Investment Company Event” (each as defined in the Subordinated Notes). Any such redemption is subject to obtaining the prior approval of the Board of Governors of the Federal Reserve System (or its designee). The redemption price with respect to any such redemption will be equal to 100% of the principal amount of the Subordinated Note, or portion thereof, to be redeemed, plus accrued but unpaid interest, if any, thereon to, but excluding, the redemption date.

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	( 8 ) STOCK-BASED COMPENSATION The Company has had a nonqualified incentive stock option plan the BancFirst Corporation Stock Option Plan (the “Employee Plan”) since May 1986. At June 30, 2021, there were 275,000 shares available for future grants. The Employee Plan will terminate on December 31, 2024, if not extended. The options vest and are exercisable beginning four years from the date of grant at the rate of 25% per year for four years. Options expire no later than the end of fifteen years from the date of grant. The option price must be no less than 100% of the fair value of the stock relating to such option at the date of grant. The Company has had the BancFirst Corporation Non-Employee Directors’ Stock Option Plan (the “Non-Employee Directors’ Plan”) since June 1999. Each non-employee director is granted an option for 10,000 shares. At June 30, 2021, there were 50,000 shares available for future grants. The Non-Employee Directors’ Plan will terminate on December 31, 2024, if not extended. The options vest and are exercisable beginning one year from the date of grant at the rate of 25% per year for four years, and expire no later than the end of fifteen years from the date of grant. The option price must be no less than 100% of the fair value of the stock relating to such option at the date of grant. The Company currently uses newly issued shares for stock option exercises, but reserves the right to use shares purchased under the Company’s Stock Repurchase Program (the “SRP”) in the future. Although not required or expected, the Company may settle some options in cash on a limited basis at the discretion of the Company. During the six months ended June 30, 2021, the Company had cash settlements for 121,330 shares for a total net cash settlement of options of $5.5 million that did not increase the outstanding shares of the Company. The following table is a summary of the activity under both the Employee Plan and the Non-Employee Directors’ Plan: Wgtd. Avg. Wgtd. Avg. Remaining Aggregate Exercise Contractual Intrinsic Options Price Term Value (Dollars in thousands, except option data) Six Months Ended June 30, 2021 Outstanding at December 31, 2020 1,343,080 $ 35.28 Options granted 53,000 69.57 Options exercised (183,830 ) 23.82 Options canceled, forfeited, or expired (5,000 ) 44.23 Outstanding at June 30, 2021 1,207,250 38.49 8.67 Yrs $ 28,896 Exercisable at June 30, 2021 596,750 26.68 7.27 Yrs $ 21,336 The following table has additional information regarding options exercised under both the Employee Plan and the Non-Employee Directors’ Plan: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 (Dollars in thousands) (Dollars in thousands) Total intrinsic value of options exercised $ 557 $ 337 $ 7,860 $ 726 Cash received from options exercised 413 303 4,379 504 Tax benefit realized from options exercised 142 86 2,002 185 The fair value of each option grant is estimated on the date of grant using the Black-Scholes option-pricing model and is based on certain assumptions including risk-free rate of return, dividend yield, stock price volatility and the expected term. The fair value of each option is expensed over its vesting period. The following table is a summary of the Company’s recorded stock-based compensation expense: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 (Dollars in thousands) (Dollars in thousands) Stock-based compensation expense $ 473 $ 406 $ 1,049 $ 832 Tax benefit 114 103 252 212 Stock-based compensation expense, net of tax $ 359 $ 303 $ 797 $ 620 The Company will continue to amortize the unearned stock-based compensation expense over the remaining vesting period of approximately seven years. The following table shows the unearned stock-based compensation expense: June 30, 2021 (Dollars in thousands) Unearned stock-based compensation expense $ 5,417 The following table shows the assumptions used for computing stock-based compensation expense under the fair value method on options granted during the periods presented: Six Months Ended June 30, 2021 2020 Weighted average grant-date fair value per share of options granted $ 23.74 $ 10.63 Risk-free interest rate 1.34 to 1.74% 0.66 to1.13% Dividend yield 2.00% 2.00% Stock price volatility 35.55 to 36.01% 22.84 to 33.56% Expected term 10 Yrs 10 Yrs The risk-free interest rate is determined by reference to the spot zero-coupon rate for the U.S. Treasury security with a maturity similar to the expected term of the options. The dividend yield is the expected yield for the expected term. The stock price volatility is estimated from the recent historical volatility of the Company’s stock. The expected term is estimated from the historical option exercise experience. The Company accounts for forfeitures as they occur. The Company has had the BancFirst Corporation Directors’ Deferred Stock Compensation Plan (the “Deferred Stock Compensation Plan”) since May 1999. As of June 30, 2021, there are 40,000 shares available for future issuance under the Deferred Stock Compensation Plan. The Deferred Stock Compensation Plan will terminate on December 31, 2024, if not extended. Under the plan, directors and members of the community advisory boards of the Company and its subsidiaries may defer up to 100% of their board fees. They are credited for each deferral with a number of stock units based on the current market price of the Company’s stock, which accumulate in an account until such time as the director or community board member terminates serving as a board member. Shares of common stock of the Company are then distributed to the terminating director or community board member based upon the number of stock units accumulated in his or her account. There were 2,161 and 1,307 shares of common stock distributed from the Deferred Stock Compensation Plan during the six months ended June 30, 2021 and June 30, 2020, respectively. A summary of the accumulated stock units is as follows: June 30, December 31, 2021 2020 Accumulated stock units 150,118 148,278 Average price $ 29.61 $ 28.57

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Stockholders' Equity	( 9 ) STOCKHOLDERS’ EQUITY In November 1999, the Company adopted the SRP. The SRP may be used as a means to increase earnings per share and return on equity. In addition, the SRP may be used to purchase treasury stock for the exercise of stock options or for distributions under the Deferred Stock Compensation Plan, to provide liquidity for optionees to dispose of stock from exercises of their stock options and to provide liquidity for stockholders wishing to sell their stock. All shares repurchased under the SRP have been retired and not held as treasury stock. The timing, price and amount of stock repurchases under the SRP may be determined by management and approved by the Company’s Executive Committee. The following table is a summary of the shares under the program: Six Months Ended June 30, 2021 2020 Number of shares repurchased — 59,284 Average price of shares repurchased $ — $ 52.26 Shares remaining to be repurchased 62,782 62,782 The Company, BancFirst and Pegasus Bank are subject to risk-based capital guidelines issued by the Board of Governors of the Federal Reserve System and the Federal Deposit Insurance Corporation (“FDIC”). These guidelines are used to evaluate capital adequacy and involve both quantitative and qualitative evaluations of the Company’s, BancFirst’s and Pegasus Bank’s assets, liabilities and certain off-balance-sheet items calculated under regulatory practices. Failure to meet the minimum capital requirements can initiate certain mandatory or discretionary actions by the regulatory agencies that could have a direct material effect on the Company’s financial statements. Management believes that as of June 30, 2021, the Company, BancFirst and Pegasus Bank met all capital adequacy requirements to which they are subject. The actual and required capital amounts and ratios are shown in the following table: Required To Be Well For Capital With Capitalized Under Adequacy Capital Conservation Prompt Corrective Actual Purposes Buffer Action Provisions Amount Ratio Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of June 30, 2021: Total Capital (to Risk Weighted Assets)- BancFirst Corporation $ 1,123,056 17.35% $ 517,721 8.00% $ 679,508 10.50% N/A N/A BancFirst 954,496 16.23% 470,400 8.00% 617,400 10.50% $ 588,000 10.00% Pegasus Bank 76,186 12.61% 48,317 8.00% 63,416 10.50% 60,396 10.00% Common Equity Tier 1 Capital (to Risk Weighted Assets)- BancFirst Corporation $ 956,969 14.79% $ 291,218 4.50% $ 453,006 7.00% N/A N/A BancFirst 860,924 14.64% 264,600 4.50% 411,600 7.00% $ 382,200 6.50% Pegasus Bank 71,113 11.77% 27,178 4.50% 42,277 7.00% 39,257 6.50% Tier 1 Capital (to Risk Weighted Assets)- BancFirst Corporation $ 982,969 15.19% $ 388,291 6.00% $ 550,078 8.50% N/A N/A BancFirst 880,924 14.98% 352,800 6.00% 499,800 8.50% $ 470,400 8.00% Pegasus Bank 71,113 11.77% 36,238 6.00% 51,337 8.50% 48,317 8.00% Tier 1 Capital (to Total Assets)- BancFirst Corporation $ 982,969 9.23% $ 425,962 4.00% N/A N/A N/A N/A BancFirst 880,924 9.13% 385,803 4.00% N/A N/A $ 482,254 5.00% Pegasus Bank 71,113 7.15% 39,786 4.00% N/A N/A 49,733 5.00% As of June 30, 2021, the most recent notification from the Federal Reserve Bank of Kansas City and the FDIC categorized BancFirst and Pegasus Bank as “well capitalized” under the prompt corrective action provisions. The Common Equity Tier 1 Capital of the Company, BancFirst and Pegasus Bank includes common stock and related paid-in capital and retained earnings. In connection with the adoption of the Basel III Capital Rules, the election was made to opt-out of the requirement to include most components of accumulated other comprehensive income in Common Equity Tier 1 Capital. Common Equity Tier 1 Capital for the Company, BancFirst and Pegasus Bank is reduced by goodwill and other intangible assets, net of associated deferred tax liabilities. The Company’s trust preferred securities have continued to be included in Tier 1 capital, as the Company’s total assets do not exceed $ 15 billion. There are no conditions or events since the most recent notification of BancFirst and Pegasus Bank’s capital category that management believes would materially change its category under capital requirements existing as of the report date. In April 2020, the Company began originating loans to qualified small businesses under the PPP administered by the SBA. Federal bank regulatory agencies have issued an interim final rule that permits banks to neutralize the regulatory capital effects of participating in the Paycheck Protection Program Lending Facility (the “PPP Facility”) and clarify that PPP loans have a zero percent risk weight under applicable risk-based capital rules. Specifically, a bank may exclude all PPP loans pledged as collateral to the PPP Facility from its average total consolidated assets for the purposes of calculating its leverage ratio, while PPP loans that are not pledged as collateral to the PPP Facility are included. The PPP loans the Company originated in 2020 and 2021 are included in the calculation of the Company’s leverage ratio as of June 30, 2021 as the Company did not utilize the PPP Facility for funding purposes. On June 17, 2021, the Company completed a private placement, under Regulation D of the Securities Act of 1933, of $60 million aggregate principal amount of Subordinated Notes. The Subordinated Notes have been structured to qualify as Tier 2 capital under bank regulatory guidelines.

Net Income Per Common Share

Net Income Per Common Share	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Net Income Per Common Share	( 10 ) NET INCOME PER COMMON SHARE Basic and diluted net income per common share are calculated as follows: Income (Numerator) Shares (Denominator) Per Share Amount (Dollars in thousands, except per share data) Three Months Ended June 30, 2021 Basic Income available to common stockholders $ 48,192 32,779,227 $ 1.47 Dilutive effect of stock options — 626,696 Diluted Income available to common stockholders plus assumed exercises of stock options $ 48,192 33,405,923 $ 1.45 Three Months Ended June 30, 2020 Basic Income available to common stockholders $ 20,730 32,651,262 $ 0.64 Dilutive effect of stock options — 424,231 Diluted Income available to common stockholders plus assumed exercises of stock options $ 20,730 33,075,493 $ 0.63 Six Months Ended June 30, 2021 Basic Income available to common stockholders $ 90,712 32,768,102 $ 2.77 Dilutive effect of stock options — 639,591 Diluted Income available to common stockholders plus assumed exercises of stock options $ 90,712 33,407,693 $ 2.72 Six Months Ended June 30, 2020 Basic Income available to common stockholders $ 43,338 32,665,425 $ 1.33 Dilutive effect of stock options — 531,996 Diluted Income available to common stockholders plus assumed exercises of stock options $ 43,338 33,197,421 $ 1.31 The following table shows the number and average exercise price of options that were excluded from the computation of diluted net income per common share for each period because the options were anti-dilutive for the period: Shares Three Months Ended June 30, 2021 43,093 Three Months Ended June 30, 2020 448,016 Six Months Ended June 30, 2021 108,055 Six Months Ended June 30, 2020 424,939

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	( 1 1 ) FAIR VALUE MEASUREMENTS Accounting standards define fair value as the price that would be received to sell an asset or the price paid to transfer a liability in the principal or most advantageous market available to the entity in an orderly transaction between market participants on the measurement date. FASB Accounting Standards Codification (“ASC”) Topic 820 establishes a fair value hierarchy for valuation inputs that gives the highest priority to quoted prices in active markets for identical assets or liabilities and the lowest priority to unobservable inputs. The fair value hierarchy is as follows: • Level 1 Inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities in active markets. • Level 2 Inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset and liability, either directly or indirectly, for substantially the full term of the financial instrument. • 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 values are determined using pricing models, discounted cash flow methodologies, or similar techniques, as well as instruments for which the determination of fair value requires significant management judgment or estimation. This category includes certain collaterally dependent loans, repossessed assets, other real estate owned, goodwill and other intangible assets. Financial Assets and Financial Liabilities Measured at Fair Value on a Recurring Basis A description of the valuation methodologies and key inputs used to measure financial assets and financial liabilities at fair value on a recurring basis, as well as the general classification of such instruments pursuant to the valuation hierarchy, is set forth below. These valuation methodologies were applied to the following categories of the Company’s financial assets and financial liabilities. Debt Securities Available for Sale Debt securities classified as available for sale are reported at fair value. U.S. Treasuries are valued using Level 1 inputs. Other debt securities available for sale including U.S. federal agencies, registered mortgage backed debt securities and state and political subdivisions are valued using prices from an independent pricing service utilizing Level 2 data. The fair value measurements consider observable data that may include dealer quotes, market spreads, cash flows, the U.S. Treasury yield curve, live trading levels, trade execution data, market consensus prepayment speeds, credit information and the bond’s terms and conditions, among other things. The Company also invests in private label mortgage backed debt securities for which observable information is not readily available. These debt securities are reported at fair value utilizing Level 3 inputs. For these debt securities, management determines the fair value based on replacement cost, the income approach or information provided by outside consultants or lead investors. Discount rates are primarily based on reference to interest rate spreads on comparable debt securities of similar duration and credit rating as determined by the nationally recognized rating agencies adjusted for a lack of trading volume. Significant unobservable inputs are developed by investment securities professionals involved in the active trading of similar debt securities. The Company reviews the prices for Level 1 and Level 2 debt securities supplied by the independent pricing service for reasonableness and to ensure such prices are aligned with traditional pricing matrices. In general, the Company does not purchase investment portfolio debt securities that are esoteric or that have complicated structures. The Company’s portfolio primarily consists of traditional investments including U.S. Treasury obligations, federal agency mortgage pass-through debt securities, general obligation municipal bonds and a small amount of municipal revenue bonds. Pricing for such instruments is fairly generic and is easily obtained. For in-state bond issues that have relatively low issue sizes and liquidity, the Company utilizes the same parameters for pricing mentioned in the preceding paragraph adjusted for the specific issue. Periodically, the Company will validate prices supplied by the independent pricing service by comparison to prices obtained from third party sources. The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of the periods presented, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value: Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (Dollars in thousands) June 30, 2021 Debt securities available for sale: U.S. Treasury $ 471,842 $ — $ — $ 471,842 U.S. federal agencies — 25,595 — 25,595 Mortgage-backed securities — 38,769 — 38,769 States and political subdivisions — 10,781 320 11,101 Asset backed securities — 13,476 — 13,476 December 31, 2020 Debt securities available for sale: U.S. Treasury $ 475,236 $ — $ — $ 475,236 U.S. federal agencies — 19,638 — 19,638 Mortgage-backed securities — 15,696 — 15,696 States and political subdivisions — 28,793 155 28,948 Asset backed securities — — 12,714 12,714 The changes in Level 3 assets measured at estimated fair value on a recurring basis during the periods presented were as follows: Six Months Ended June 30, Twelve Months Ended December 31, 2021 2020 (Dollars in thousands) Balance at the beginning of the year $ 12,869 $ 12,714 Transfers (to)/from level 2 (12,714 ) 1,643 Purchases 240 — Settlements (75 ) (1,473 ) Total unrealized losses — (15 ) Balance at the end of the period $ 320 $ 12,869 The Company’s policy is to recognize transfers in and transfers out of Levels 1, 2 and 3 as of the end of the reporting period. During the six months ended June 30, 2021, the Company transferred debt securities from Level 3 to Level 2 due to a review of the pricing models that determined some asset backed debt securities to be Level 2. During the year ended December 31, 2020, the Company transferred debt securities from Level 2 to Level 3 due to a review of the pricing models that determined some state and political subdivisions bonds to be Level 3. Financial Assets and Financial Liabilities Measured at Fair Value on a Nonrecurring Basis Certain financial assets and financial liabilities are measured at fair value on a nonrecurring basis; that is, the instruments are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (for example, when there is evidence of impairment). These financial assets and financial liabilities are reported at fair value utilizing Level 3 inputs. The Company invests in equity securities without readily determinable fair values and utilizes Level 3 inputs. These equity securities are reported at cost minus impairment, if any, plus or minus changes resulting from observable price changes in orderly transactions for the identical or a similar investment of the same issuer. The realized and unrealized gains and losses are reported as securities transactions in the noninterest income section of the consolidated statements of comprehensive income. Collateral dependent loans are reported at the fair value of the underlying collateral if repayment is dependent on liquidation of the collateral. When management determines that foreclosure is probable or when the borrower is experiencing financial difficulty at the reporting date and repayment is expected to be provided substantially through the operation or sale of the collateral, expected credit losses are based on the fair value of the collateral at the reporting date, adjusted for selling costs as appropriate. In no case does the fair value of a collateral dependent loan exceed the fair value of the underlying collateral. The collateral dependent loans are adjusted to fair value through a specific allocation of the allowance for credit losses or a direct charge-down of the loan. Repossessed assets, upon initial recognition, are measured and adjusted to fair value through a charge-off to the allowance for possible credit losses based upon the fair value of the repossessed asset. Other real estate owned is revalued at fair value subsequent to initial recognition, with any losses recognized in net expense from other real estate owned. The following table summarizes assets measured at fair value on a nonrecurring basis during the period presented. The fair value represents end of period values, which approximate fair value measurements that occurred on various measurement dates throughout the period: Total Fair Value Level 3 (Dollars in thousands) As of and for the Year-to-date Period Ended June 30, 2021 Equity securities $ 21,548 Collateral dependent loans 867 Repossessed assets 50 Other real estate owned 8,009 As of and for the Year-to-date Period Ended December 31, 2020 Equity securities $ 21,203 Collateral dependent loans 11,347 Repossessed assets 291 Other real estate owned 32,066 Estimated Fair Value of Financial Instruments The Company is required under current authoritative accounting guidance to disclose the estimated fair value of their financial instruments that are not recorded at fair value. For the Company, as for most financial institutions, substantially all of its assets and liabilities are considered financial instruments. A financial instrument is defined as cash, evidence of an ownership interest in an entity or a contract that creates a contractual obligation or right to deliver or receive cash or another financial instrument from a second entity. The following methods and assumptions were used to estimate the fair value of each class of financial instruments: Cash and Cash Equivalents Include: Cash and Due from Banks and Interest-Bearing Deposits with Banks The carrying amount of these short-term instruments is based on a reasonable estimate of fair value. Debt Securities Held for Investment For debt securities held for investment, which are generally traded in secondary markets, fair values are based on quoted market prices or dealer quotes, if available. If a quoted market price is not available, fair value is estimated using quoted market prices for similar debt securities making adjustments for credit or liquidity if applicable. Loans Held For Sale The Company originates mortgage loans to be sold. At the time of origination, the acquiring bank has already been determined and the terms of the loan, including interest rate, have already been set by the acquiring bank, allowing the Company to originate the loan at fair value. Mortgage loans are generally sold within 30 days of origination. Loans held for sale are valued using Level 2 inputs. Gains or losses recognized upon the sale of the loans are determined on a specific identification basis. At December 31, 2020, the Company’s principal subsidiary bank, BancFirst, had approximately $21.6 million in loans held for sale at its Hugo, Oklahoma branch that were sold to AmeriState Bank in Atoka, Oklahoma in the first quarter of 2021. Loans To determine the fair value of loans, the Company uses an exit price calculation, which takes into account factors such as liquidity, credit and the nonperformance risk of loans. For certain homogeneous categories of loans, such as some residential mortgages, fair values are estimated using the quoted market prices for securities backed by similar loans, adjusted for differences in loan characteristics. The fair values of other types of loans are estimated by discounting the future cash flows using the current rates at which similar loans would be made to borrowers with similar credit ratings and for the same remaining maturities. Deposits The fair values of transaction and savings accounts are the amounts payable on demand at the reporting date. The fair values of fixed-maturity certificates of deposit are estimated using the rates currently offered for deposits of similar remaining maturities. Short-Term Borrowings The amounts payable on these short-term instruments are reasonable estimates of fair value. Subordinated Debt The fair values of subordinated debt are estimated using the rates that would be charged for subordinated debt of similar remaining maturities. Loan Commitments and Letters of Credit The fair values of commitments are estimated using the fees currently charged to enter into similar agreements, taking into account the terms of the agreements. The fair values of letters of credit are based on fees currently charged for similar agreements. The estimated fair values of the Company’s financial instruments that are reported at amortized cost in the Company’s consolidated balance sheets, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value, are as follows: June 30, December 31, 2021 2020 Carrying Amount Fair Value Carrying Amount Fair Value (Dollars in thousands) FINANCIAL ASSETS Level 2 inputs: Cash and cash equivalents $ 3,641,398 $ 3,641,398 $ 1,616,912 $ 1,616,912 Debt securities held for investment 43 45 59 62 Loans held for sale 16,032 16,032 53,719 53,719 Level 3 inputs: Debt securities held for investment 2,945 2,945 2,905 2,922 Loans, net of allowance for credit losses 6,107,267 6,108,907 6,303,140 6,347,803 FINANCIAL LIABILITIES Level 2 inputs: Deposits 9,728,389 9,817,785 8,064,704 8,084,695 Short-term borrowings 3,100 3,100 1,100 1,100 Subordinated debt 85,959 89,270 26,804 30,535 OFF-BALANCE SHEET FINANCIAL INSTRUMENTS Loan commitments 3,313 3,115 Letters of credit 567 722 Non-financial Assets and Non-financial Liabilities Measured at Fair Value The Company has no non-financial assets or non-financial liabilities measured at fair value on a recurring basis. Certain non-financial assets and non-financial liabilities measured at fair value on a nonrecurring basis include intangible assets and other non-financial long-lived assets measured at fair value and adjusted for impairment. These items are evaluated at least annually for impairment. The overall levels of non-financial assets and non-financial liabilities measured at fair value on a nonrecurring basis were not considered to be significant to the Company at June 30, 2021 or December 31, 2020.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Segment Information	(12) SEGMENT INFORMATION The Company evaluates its performance with an internal profitability measurement system that measures the profitability of its business units on a pre-tax basis. The five principal business units are metropolitan banks, community banks, Pegasus Bank, other financial services and executive, operations and support. Metropolitan banks, community banks and Pegasus Bank offer traditional banking products such as commercial and retail lending and a full line of deposit accounts. Metropolitan banks consist of banking locations in the metropolitan Oklahoma City and Tulsa areas. Community banks consist of banking locations in communities throughout Oklahoma. Pegasus Bank consists of banking locations in the Dallas metropolitan area. Other financial services are specialty product business units including guaranteed small business lending, residential mortgage lending, trust services, securities brokerage, electronic banking and insurance. The executive, operations and support groups represent executive management, operational support and corporate functions that are not allocated to the other business units. The results of operations and selected financial information for the five business units are as follows: Metropolitan Banks Community Banks Pegasus Bank Other Financial Services Executive, Operations & Support Eliminations Consolidated (Dollars in thousands) Three Months Ended June 30, 2021 Net interest income $ 19,848 $ 45,024 $ 5,808 $ 11,457 $ 9 $ 217 $ 82,363 Noninterest income 3,669 16,197 355 10,913 62,025 (48,541 ) 44,618 Income before taxes 17,602 36,514 1,947 5,220 49,790 (48,166 ) 62,907 Three Months Ended June 30, 2020 Net interest income $ 22,310 $ 43,917 $ 4,976 $ 5,905 $ 100 $ — $ 77,208 Noninterest income 4,571 13,841 121 9,328 25,774 (21,553 ) 32,082 Income before taxes 3,613 15,532 1,345 7,786 18,232 (21,202 ) 25,306 Six Months Ended June 30, 2021 Net interest income $ 39,181 $ 87,794 $ 11,167 $ 21,339 $ (398 ) $ 486 $ 159,569 Noninterest income 8,813 31,173 739 22,488 111,756 (90,416 ) 84,553 Income before taxes 31,526 66,283 3,592 11,171 92,130 (89,617 ) 115,085 Six Months Ended June 30, 2020 Net interest income $ 44,494 $ 88,415 $ 10,584 $ 7,488 $ 300 $ — $ 151,281 Noninterest income 9,271 29,694 252 20,218 53,257 (45,465 ) 67,227 Income before taxes 14,026 39,968 2,943 13,545 27,635 (44,561 ) 53,556 Total Assets: June 30, 2021 $ 3,247,686 $ 6,572,642 $ 966,809 $ 113,126 $ 1,437,732 $ (1,322,708 ) $ 11,015,287 December 31, 2020 2,729,886 5,527,611 919,572 137,122 1,073,507 (1,175,341 ) 9,212,357 The financial information for each business unit is presented on the basis used internally by management to evaluate performance and allocate resources. The Company utilizes a transfer pricing system to allocate the benefit or cost of funds provided or used by the various business units. Certain services provided by the support group to other business units, such as item processing, are allocated at rates approximating the cost of providing the services. Eliminations are adjustments to consolidate the business units and companies.

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited interim consolidated financial statements include the accounts of BancFirst Corporation, Council Oak Partners, LLC, BancFirst Insurance Services, Inc., Pegasus Bank and BancFirst and its subsidiaries. The principal operating subsidiaries of BancFirst are Council Oak Investment Corporation, Council Oak Real Estate, Inc., BFTower, LLC, BFC-PNC LLC, and BancFirst Agency, Inc. All significant intercompany accounts and transactions have been eliminated. Assets held in a fiduciary or agency capacity are not assets of the Company and, accordingly, are not included in the unaudited interim consolidated financial statements. The accompanying unaudited interim consolidated financial statements and notes are presented in accordance with U.S. GAAP for interim financial information and the instructions for Form 10-Q adopted by the Securities and Exchange Commission (“SEC”). The information contained in the financial statements and footnotes included in BancFirst Corporation’s Annual Report on Form 10-K for the year ended December 31, 2020, should be referred to in connection with these unaudited interim consolidated financial statements. Operating results for the interim periods disclosed herein are not necessarily indicative of the results that may be expected for a full year or any future period. The unaudited interim consolidated financial statements contained herein reflect all adjustments, which are, in the opinion of management, necessary to provide a fair statement of the financial position and results of operations of the Company for the interim periods presented. All such adjustments are of a normal and recurring nature.
Use of Estimates in the Preparation of Financial Statements	Use of Estimates in the Preparation of Financial Statements The preparation of financial statements in conformity with accounting principles generally accepted in the United States inherently involves the use of estimates and assumptions that affect the amounts reported in the financial statements and the related disclosures. These estimates relate principally to the determination of the allowance for credit losses, income taxes, the fair value of financial instruments and the valuation of intangibles. Such estimates and assumptions may change over time and actual amounts realized may differ from those reported.

Securities (Tables)

Securities (Tables)	6 Months Ended
	Jun. 30, 2021
Investments Debt And Equity Securities [Abstract]
Summary of Amortized Cost and Estimated Fair Values of Debt Securities Held for Investment	The following table summarizes the amortized cost and estimated fair values of debt securities held for investment: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value June 30, 2021 (Dollars in thousands) Mortgage backed securities (1) $ 43 $ 2 $ — $ 45 States and political subdivisions 2,445 — — 2,445 Other securities 500 — — 500 Total $ 2,988 $ 2 $ — $ 2,990 December 31, 2020 Mortgage backed securities (1) $ 59 $ 3 $ — $ 62 States and political subdivisions 2,405 18 (1 ) 2,422 Other securities 500 — — 500 Total $ 2,964 $ 21 $ (1 ) $ 2,984
Summary of Amortized Cost and Estimated Fair Values of Debt Securities Available for Sale	The following table summarizes the amortized cost and estimated fair values of debt securities available for sale: Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value June 30, 2021 (Dollars in thousands) U.S. treasuries $ 465,762 $ 6,680 $ (600 ) $ 471,842 U.S. federal agencies 25,273 324 (2 ) 25,595 Mortgage backed securities (1) 38,407 471 (109 ) 38,769 States and political subdivisions 10,874 227 — 11,101 Asset backed securities 13,346 130 — 13,476 Total $ 553,662 $ 7,832 $ (711 ) $ 560,783 December 31, 2020 U.S. treasuries $ 465,416 $ 9,820 $ — $ 475,236 U.S. federal agencies 19,697 1 (60 ) 19,638 Mortgage backed securities (1) 15,268 428 — 15,696 States and political subdivisions 28,571 377 — 28,948 Asset backed securities 13,337 — (623 ) 12,714 Total $ 542,289 $ 10,626 $ (683 ) $ 552,232 (1) Primarily consists of FHLMC, FNMA, GNMA and mortgage backed securities through U.S. agencies.
Maturity of Debt Securities	The maturities of debt securities held for investment and available for sale are summarized in the following table using contractual maturities. Actual maturities may differ from contractual maturities due to obligations that are called or prepaid. For purposes of the maturity table, mortgage-backed securities, which are not due at a single maturity date, have been presented at their contractual maturity. June 30, 2021 December 31, 2020 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value (Dollars in thousands) Held for Investment Contractual maturity of debt securities: Within one year $ 576 $ 576 $ 807 $ 809 After one year but within five years 2,407 2,409 2,091 2,110 After five years but within ten years 4 4 65 64 After ten years 1 1 1 1 Total $ 2,988 $ 2,990 $ 2,964 $ 2,984 Available for Sale Contractual maturity of debt securities: Within one year $ 110,293 $ 111,495 $ 339,752 $ 341,102 After one year but within five years 373,494 378,554 162,401 171,135 After five years but within ten years 9,925 10,467 3,753 3,910 After ten years 59,950 60,267 36,383 36,085 Total debt securities $ 553,662 $ 560,783 $ 542,289 $ 552,232
Company's Book Value of Pledged Debt Securities	The following table is a summary of the Company’s book value of securities that were pledged as collateral for public funds on deposit, repurchase agreements and for other purposes as required or permitted by law: June 30, 2021 December 31, 2020 (Dollars Book value of pledged securities $ 498,877 $ 490,833

Loans Held for Investment and_2

Loans Held for Investment and Allowance for Credit Losses on Loans (Tables)	6 Months Ended
	Jun. 30, 2021
Receivables [Abstract]
Summary of Loans Held for Investment by Portfolio Segment	Loans held for investment are summarized by portfolio segment as follows: June 30, 2021 December 31, 2020 Amount Amount (Dollars in thousands) BancFirst Real estate: Commercial real estate owner occupied $ 661,530 $ 641,987 Commercial real estate non-owner occupied 989,560 971,158 Construction and development < 60 months 297,205 229,615 Construction residential real estate < 60 months 208,210 206,195 Residential real estate first lien 865,557 853,316 Residential real estate all other 163,290 168,081 Farmland 269,008 252,958 Commercial and agricultural non-real estate 1,105,777 1,159,810 Consumer non-real estate 371,557 355,405 Oil and gas 130,459 179,355 Other loans (2) 543,034 822,078 Pegasus Bank 586,043 554,548 Total (1) $ 6,191,230 $ 6,394,506 (1) Excludes accrued interest receivable of $22.9 million at June 30, 2021 and $26.0 million at December 31, 2020, that is recorded in accrued interest receivable and other assets. (2) Includes PPP loans held for investment of $368.6 million, net of unamortized processing fees of $16.6 million at June 30, 2021 and $652.7 million, net of unamortized processing fees of $14.5 million at December 31, 2020.
Summary of Energy Loans	BancFirst and Pegasus Bank’s commercial and agricultural non-real estate and oil and gas loan categories include upstream and midstream energy loans, and loans to companies that provide ancillary services to the energy industry, such as transportation, wellsite preparation contractors and equipment manufacturers. Energy loans are summarized as follows: June 30, 2021 December 31, 2020 Amount Amount (Dollars in thousands) BancFirst energy loans Upstream $ 141,651 $ 190,788 Midstream 37,134 49,734 Ancillary services 74,919 59,410 Pegasus Bank energy loans Upstream 127,736 107,103 Midstream 8,797 11,047 Ancillary services 14,049 12,503 Total $ 404,286 $ 430,585
Summary of Troubled Debt Restructurings and Other Real Estate Owned and Repossessed Assets	The following is a summary of troubled debt restructurings and other real estate owned and repossessed assets: June 30, December 31, 2021 2020 (Dollars in thousands) Troubled debt restructurings $ 7,485 $ 7,784 Other real estate owned and repossessed assets $ 40,183 $ 32,480
Summary of Amounts Included in Nonaccrual Loans Segregated by Portfolio Segment	The following table is a summary of amounts included in nonaccrual loans, segregated by portfolio segment. June 30, 2021 December 31, 2020 (Dollars in thousands) BancFirst Real estate: Commercial real estate owner occupied $ 2,572 $ 1,404 Commercial real estate non-owner occupied 422 4,719 Construction and development < 60 months 88 95 Construction residential real estate < 60 months — — Residential real estate first lien 3,518 3,615 Residential real estate all other 1,188 1,362 Farmland 6,354 7,901 Commercial and agricultural non-real estate 13,185 12,782 Consumer non-real estate 188 268 Oil and gas — — Other loans 2,287 5,399 Pegasus Bank — — Total $ 29,802 $ 37,545
Age Analysis of Loans Held for Investments	Loans are considered past due if the required principal and interest payments have not been received as of the date such payments were due. The following table presents an age analysis of our loans held for investment: Age Analysis of Past Due Loans 30-59 Days Past Due 60-89 Days Past Due 90 Days and Greater Total Past Due Loans Current Loans Total Loans Accruing Loans 90 Days or More Past Due (Dollars in thousands) As of June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 604 $ — $ 1,012 $ 1,616 $ 659,914 $ 661,530 $ 80 Commercial real estate non-owner occupied 205 — 112 317 989,243 989,560 37 Construction and development < 60 months 53 1,605 137 1,795 295,410 297,205 137 Construction residential real estate < 60 months 103 — — 103 208,107 208,210 — Residential real estate first lien 3,639 447 3,989 8,075 857,482 865,557 2,070 Residential real estate all other 1,195 40 1,536 2,771 160,519 163,290 458 Farmland 1,036 989 4,327 6,352 262,656 269,008 157 Commercial and agricultural non-real estate 3,780 2,821 8,393 14,994 1,090,783 1,105,777 638 Consumer non-real estate 1,620 353 221 2,194 369,363 371,557 190 Oil and gas — — — — 130,459 130,459 — Other loans 1,472 478 2,102 4,052 538,982 543,034 619 Pegasus Bank — — — — 586,043 586,043 — Total $ 13,707 $ 6,733 $ 21,829 $ 42,269 $ 6,148,961 $ 6,191,230 $ 4,386 As of December 31, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 1,096 $ 108 $ 1,164 $ 2,368 $ 639,619 $ 641,987 $ — Commercial real estate non-owner occupied 323 — 34 357 970,801 971,158 35 Construction and development < 60 months 511 86 — 597 229,018 229,615 — Construction residential real estate < 60 months 1,106 — 282 1,388 204,807 206,195 282 Residential real estate first lien 5,428 1,463 2,978 9,869 843,447 853,316 945 Residential real estate all other 520 55 1,606 2,181 165,900 168,081 384 Farmland 1,297 344 6,223 7,864 245,094 252,958 135 Commercial and agricultural non-real estate 2,788 1,794 4,345 8,927 1,150,883 1,159,810 465 Consumer non-real estate 2,154 501 534 3,189 352,216 355,405 386 Oil and gas — — — — 179,355 179,355 — Other loans 951 1,223 6,618 8,792 813,286 822,078 2,170 Pegasus Bank — — — — 554,548 554,548 — Total $ 16,174 $ 5,574 $ 23,784 $ 45,532 $ 6,348,974 $ 6,394,506 $ 4,802
Gross Loans Held for Investment by Year of Origination and Internally Assigned Credit Grades	The following table summarizes our gross loans held for investment by year of origination and internally assigned credit grades as of June 30, 2021: Term Loans Amortized Cost Basis by Origination Year 2021 2020 2019 2018 2017 Prior Revolving Loans Amortized Cost Basis Total (Dollars in thousands) As of June 30, 2021 BancFirst Commercial real estate owner occupied Grade 1 $66,327 $135,671 $83,146 $53,559 $36,961 $112,760 $11,507 $499,931 Grade 2 17,354 38,028 30,351 10,695 9,710 40,707 4,904 151,749 Grade 3 3 3,905 27 266 476 2,621 — 7,298 Grade 4 349 — 921 539 — 436 307 2,552 Total commercial real estate owner occupied loans 84,033 177,604 114,445 65,059 47,147 156,524 16,718 661,530 Commercial real estate non-owner occupied Grade 1 95,260 227,302 147,192 62,169 61,402 137,491 18,024 748,840 Grade 2 16,345 59,541 44,838 37,862 19,357 43,884 4,657 226,484 Grade 3 7,453 — 3,412 214 1,607 865 — 13,551 Grade 4 — — 50 37 — 598 — 685 Total commercial real estate non-owner occupied loans 119,058 286,843 195,492 100,282 82,366 182,838 22,681 989,560 Construction and development < 60 months Grade 1 91,143 63,018 66,976 11,381 2,547 3,210 10,454 248,729 Grade 2 12,579 12,938 12,391 2,187 1,811 773 2,128 44,807 Grade 3 1,753 1,690 130 7 — — — 3,580 Grade 4 — — 61 8 20 — — 89 Total construction and development < 60 months 105,475 77,646 79,558 13,583 4,378 3,983 12,582 297,205 Construction residential real estate < 60 months Grade 1 101,482 69,169 52 — 20 30 7,264 178,017 Grade 2 14,182 14,919 — 109 — 437 — 29,647 Grade 3 546 — — — — — — 546 Total construction residential real estate < 60 months 116,210 84,088 52 109 20 467 7,264 208,210 Residential real estate first lien Grade 1 134,782 188,553 109,336 69,907 54,107 154,974 — 711,659 Grade 2 22,669 25,098 16,385 19,237 10,187 42,381 — 135,957 Grade 3 1,102 1,809 2,526 901 1,360 4,832 — 12,530 Grade 4 49 511 442 1,149 934 2,326 — 5,411 Total residential real estate first lien 158,602 215,971 128,689 91,194 66,588 204,513 — 865,557 Residential real estate all other Grade 1 9,847 16,428 11,139 8,009 5,157 15,276 28,321 94,177 Grade 2 746 3,263 1,743 1,325 1,137 2,367 53,510 64,091 Grade 3 272 140 410 248 718 376 1,042 3,206 Grade 4 14 211 — 579 15 652 345 1,816 Total residential real estate all other 10,879 20,042 13,292 10,161 7,027 18,671 83,218 163,290 Farmland Grade 1 26,621 46,638 25,418 18,375 13,983 35,431 7,521 173,987 Grade 2 8,767 9,048 26,148 5,702 5,457 13,424 10,709 79,255 Grade 3 2,786 2,068 1,676 300 742 1,213 1,842 10,627 Grade 4 — 1,195 — 3,187 296 183 278 5,139 Total farmland 38,174 58,949 53,242 27,564 20,478 50,251 20,350 269,008 Commercial and agricultural non-real estate Grade 1 190,653 135,726 105,770 64,491 54,567 54,870 220,348 826,425 Grade 2 38,938 47,478 29,481 11,780 3,885 18,985 68,353 218,900 Grade 3 4,900 5,500 1,706 12,010 1,858 639 21,708 48,321 Grade 4 262 1,783 1,555 599 811 1,299 5,822 12,131 Total commercial and agricultural non-real estate 234,753 190,487 138,512 88,880 61,121 75,793 316,231 1,105,777 Consumer non-real estate Grade 1 110,171 116,215 64,985 27,641 9,497 4,018 7,084 339,611 Grade 2 9,362 9,659 4,641 2,833 1,099 1,653 287 29,534 Grade 3 229 405 787 290 154 147 3 2,015 Grade 4 14 67 180 58 19 55 4 397 Total consumer non-real estate 119,776 126,346 70,593 30,822 10,769 5,873 7,378 371,557 Oil and gas Grade 1 53,326 115 59 66 — 3,444 33,676 90,686 Grade 2 10,051 3,347 69 — — — 9,419 22,886 Grade 3 16,887 — — — — — — 16,887 Total oil and gas 80,264 3,462 128 66 — 3,444 43,095 130,459 Other loans Grade 1 379,715 34,608 29,464 24,034 18,060 25,568 23,298 534,747 Grade 2 — — 250 17 2,638 2,434 820 6,159 Grade 3 — 11 225 10 1 99 199 545 Grade 4 — 137 — — 294 140 1,012 1,583 Total other loans 379,715 34,756 29,939 24,061 20,993 28,241 25,329 543,034 Pegasus Bank Grade 1 64,138 87,556 58,223 7,261 16,202 52,432 153,260 439,072 Grade 2 27,016 14,313 18,116 10,578 21,378 6,717 48,741 146,859 Grade 3 — 112 — — — — — 112 Total Pegasus Bank 91,154 101,981 76,339 17,839 37,580 59,149 202,001 586,043 Total loans held for investment $1,538,093 $1,378,175 $900,281 $469,620 $358,467 $789,747 $756,847 $6,191,230
Activity in Allowance for Credit Losses on Loans	The following table details activity in the allowance for credit losses on loans for the period presented. Allocation of a portion of the allowance to one category of loans does not preclude its availability to absorb losses in other categories. Allowance for Credit Losses Balance at beginning of period Initial allowance on loans purchased with credit deterioration Charge- offs Recoveries Net charge-offs (Benefit from) /Provision for credit losses on loans Balance at end of period (Dollars in thousands) Three Months Ended June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 6,595 $ 987 $ — $ 1 $ 1 $ (828 ) $ 6,755 Commercial real estate non-owner occupied 16,955 633 (758 ) — (758 ) (2,340 ) 14,490 Construction and development < 60 months 2,743 173 — 2 2 (25 ) 2,893 Construction residential real estate < 60 months 983 — — — — (94 ) 889 Residential real estate first lien 2,592 117 (9 ) 12 3 93 2,805 Residential real estate all other 1,873 — (30 ) 1 (29 ) 97 1,941 Farmland 3,077 643 — 1 1 (6 ) 3,715 Commercial and agricultural non-real estate 32,685 4,711 (3,433 ) 125 (3,308 ) (2,473 ) 31,615 Consumer non-real estate 3,256 8 (209 ) 86 (123 ) 174 3,315 Oil and gas 12,131 — — — — (4,314 ) 7,817 Other loans 3,190 — (9 ) — (9 ) (43 ) 3,138 Pegasus Bank 4,780 — — — — (190 ) 4,590 Total $ 90,860 $ 7,272 $ (4,448 ) $ 228 $ (4,220 ) $ (9,949 ) $ 83,963 Six Months Ended June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 7,035 $ 987 $ — $ 1 $ 1 $ (1,268 ) $ 6,755 Commercial real estate non-owner occupied 11,842 633 (796 ) — (796 ) 2,811 14,490 Construction and development < 60 months 2,560 173 — 5 5 155 2,893 Construction residential real estate < 60 months 627 — — — — 262 889 Residential real estate first lien 2,570 117 (52 ) 27 (25 ) 143 2,805 Residential real estate all other 2,230 — (46 ) 4 (42 ) (247 ) 1,941 Farmland 3,136 643 — 1 1 (65 ) 3,715 Commercial and agricultural non-real estate 32,400 4,711 (3,537 ) 151 (3,386 ) (2,110 ) 31,615 Consumer non-real estate 3,377 8 (622 ) 198 (424 ) 354 3,315 Oil and gas 17,851 — — — — (10,034 ) 7,817 Other loans 3,182 — (61 ) — (61 ) 17 3,138 Pegasus Bank 4,556 — — 1 1 33 4,590 Total $ 91,366 $ 7,272 $ (5,114 ) $ 388 $ (4,726 ) $ (9,949 ) $ 83,963 Allowance for Credit Losses Balance at beginning of period Impact of CECL adoption Initial allowance on loans purchased with credit deterioration Charge- offs Recoveries Net charge-offs Provision for /(benefit from) credit losses on loans Balance at end of period (Dollars in thousands) Three Months Ended June 30, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 4,544 $ — $ — $ (113 ) $ 1 $ (112 ) $ 2,198 $ 6,630 Commercial real estate non-owner occupied 5,935 — — — — — 3,548 9,483 Construction and development < 60 months 1,136 — — (56 ) 3 (53 ) 672 1,755 Construction residential real estate < 60 months 1,618 — — (28 ) — (28 ) 669 2,259 Residential real estate first lien 6,192 — — (66 ) 4 (62 ) 2,423 8,553 Residential real estate all other 2,292 — — (7 ) 1 (6 ) 434 2,720 Farmland 1,788 — — — — — 723 2,511 Commercial and agricultural non-real estate 33,993 — — (287 ) 66 (221 ) 264 34,036 Consumer non-real estate 3,385 — — (235 ) 57 (178 ) 1,507 4,714 Oil and gas 3,283 — — — — — 7,186 10,469 Other loans 2,751 — — — — — (238 ) 2,513 Pegasus Bank 3,163 — — 330 417 747 (53 ) 3,857 Total $ 70,080 $ — $ — $ (462 ) $ 549 $ 87 $ 19,333 $ 89,500 Six Months Ended June 30, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 5,625 $ (2,806 ) $ 432 $ (113 ) $ 1 $ (112 ) $ 3,491 $ 6,630 Commercial real estate non-owner occupied 8,358 (5,507 ) — — — — 6,632 9,483 Construction and development < 60 months 2,214 (1,056 ) — (59 ) 3 (56 ) 653 1,755 Construction residential real estate < 60 months 1,933 (778 ) — (29 ) — (29 ) 1,133 2,259 Residential real estate first lien 8,692 (3,831 ) 7 (218 ) 6 (212 ) 3,897 8,553 Residential real estate all other 2,767 (1,408 ) — (32 ) 28 (4 ) 1,365 2,720 Farmland 2,821 (1,408 ) 1 — — — 1,097 2,511 Commercial and agricultural non-real estate 13,462 13,195 62 (374 ) 83 (291 ) 7,608 34,036 Consumer non-real estate 3,252 (622 ) — (556 ) 114 (442 ) 2,526 4,714 Oil and gas 1,883 (1,346 ) — — — — 9,932 10,469 Other loans 2,632 (116 ) — — 2 2 (5 ) 2,513 Pegasus Bank 599 2,488 — (241 ) 424 183 587 3,857 Total $ 54,238 $ (3,195 ) $ 502 $ (1,622 ) $ 661 $ (961 ) $ 38,916 $ 89,500
Purchased Credit Deteriorated Loans	The Company has previously purchased loans, for which there was, at acquisition, evidence of more than insignificant deterioration of credit quality since origination. The credit-deteriorated loans purchased during the six-month periods ended June 30, 2021 and June 30, 2020 were as follows: Loans acquired with deteriorated credit quality (Dollars in thousands) For the period ended June 30, 2021 Purchase price of loans at acquisition $ 26,779 Allowance for credit losses at acquisition 7,272 Par value of acquired loans at acquisition $ 34,051 For the period ended June 30, 2020 Purchase price of loans at acquisition $ 1,761 Allowance for credit losses at acquisition 502 Par value of acquired loans at acquisition $ 2,263
Collateral-Dependent Gross Loans Held for Investment by Collateral Type and Related Specific Allocation	The following table summarizes collateral-dependent gross loans held for investment by collateral type and the related specific allocation as follows: Collateral Type Real Estate Business Assets Energy Reserves Other Assets Total Specific Allocation (Dollars in thousands) As of June 30, 2021 BancFirst Real estate: Commercial real estate owner occupied $ 645 $ — $ — $ — $ 645 $ 176 Commercial real estate non-owner occupied — — — — — — Construction and development < 60 months — — — — — — Construction residential real estate < 60 months — — — — — — Residential real estate first lien 806 — — — 806 158 Residential real estate all other 650 — — — 650 568 Farmland 3,215 — — — 3,215 1,123 Commercial and agricultural non-real estate — 5,211 — 5,188 10,399 778 Consumer non-real estate — — — 22 22 4 Oil and gas — — — — — — Other loans — 15 — — 15 15 Pegasus Bank — — — — — — Total collateral-dependent loans held for investment $ 5,316 $ 5,226 $ — $ 5,210 $ 15,752 $ 2,822 Collateral Type Real Estate Business Assets Energy Reserves Other Assets Total Specific Allocation (Dollars in thousands) As of December 31, 2020 BancFirst Real estate: Commercial real estate owner occupied $ 848 $ — $ — $ — $ 848 $ 226 Commercial real estate non-owner occupied 4,719 — — — 4,719 1,000 Construction and development < 60 months — — — — — — Construction residential real estate < 60 months — — — — — — Residential real estate first lien 860 — — — 860 151 Residential real estate all other 866 — — — 866 616 Farmland 3,258 — — — 3,258 1,114 Commercial and agricultural non-real estate — 8,460 — 413 8,873 2,813 Consumer non-real estate — — — 109 109 58 Oil and gas — — — — — — Other loans — 13 — — 13 12 Pegasus Bank 1,257 — — — 1,257 222 Total collateral-dependent loans held for investment $ 11,808 $ 8,473 $ — $ 522 $ 20,803 $ 6,212
Transfers from Loans and Premises and Equipment to Other Real Estate Owned and Repossessed Assets	Transfers from loans and premises and equipment to other real estate owned and repossessed assets during the periods presented are summarized as follows: Six Months Ended June 30, 2021 2020 (Dollars in thousands) Other real estate owned $ 9,438 $ 2,876 Repossessed assets 427 722 Total $ 9,865 $ 3,598

Intangible Assets and Goodwill

Intangible Assets and Goodwill (Tables)	6 Months Ended
	Jun. 30, 2021
Goodwill And Intangible Assets Disclosure [Abstract]
Summary of Intangible Assets	The following is a summary of intangible assets: Gross Carrying Amount Accumulated Amortization Net Carrying Amount (Dollars in thousands) As of June 30, 2021 Core deposit intangibles $ 30,849 $ (12,120 ) $ 18,729 Customer relationship intangibles 3,350 (2,796 ) 554 Total $ 34,199 $ (14,916 ) $ 19,283 As of December 31, 2020 Core deposit intangibles $ 33,411 $ (15,076 ) $ 18,335 Customer relationship intangibles 3,350 (2,686 ) 664 Total $ 36,761 $ (17,762 ) $ 18,999
Summary of Goodwill by Business Segment	The following is a summary of goodwill by business segment: Other Executive, Metropolitan Community Pegasus Financial Operations Banks Banks Bank Services & Support Consolidated (Dollars in thousands) Six months ended June 30, 2021 Balance at beginning and end of period $ 13,767 $ 61,212 $ 68,855 $ 5,464 $ 624 $ 149,922

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2021
Leases [Abstract]
Schedule of Minimum Future Commitments of Operating Leases	The following table presents minimum future commitments by year for the Company’s operating leases. Such commitments are reflected as undiscounted values and are reconciled to the discounted present value recognized on the balance sheet. June 30, 2021 (Dollars in thousands) 2021 (six months) $ 703 2022 1,212 2023 708 2024 345 2025 286 Thereafter 893 Total lease payments 4,147 Less imputed Interest (497 ) Operating lease liability $ 3,650
Scheduled of Minimum Future Contractual Rent To be Received Under The Remaining Non-Cancelable Term of Operating Leases	The following table presents the scheduled minimum future contractual rent to be received under the remaining non-cancelable term of the operating leases: June 30, 2021 (Dollars in thousands) 2021 (six months) $ 1,765 2022 2,857 2023 2,636 2024 2,571 2025 1,946 2026-2031 6,146 Total future minimum lease payments $ 17,921

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Activity Under Stock Option Plan	The following table is a summary of the activity under both the Employee Plan and the Non-Employee Directors’ Plan: Wgtd. Avg. Wgtd. Avg. Remaining Aggregate Exercise Contractual Intrinsic Options Price Term Value (Dollars in thousands, except option data) Six Months Ended June 30, 2021 Outstanding at December 31, 2020 1,343,080 $ 35.28 Options granted 53,000 69.57 Options exercised (183,830 ) 23.82 Options canceled, forfeited, or expired (5,000 ) 44.23 Outstanding at June 30, 2021 1,207,250 38.49 8.67 Yrs $ 28,896 Exercisable at June 30, 2021 596,750 26.68 7.27 Yrs $ 21,336
Options Exercised Under Stock Option Plan	The following table has additional information regarding options exercised under both the Employee Plan and the Non-Employee Directors’ Plan: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 (Dollars in thousands) (Dollars in thousands) Total intrinsic value of options exercised $ 557 $ 337 $ 7,860 $ 726 Cash received from options exercised 413 303 4,379 504 Tax benefit realized from options exercised 142 86 2,002 185
Stock-based Employee Compensation Expense	The following table is a summary of the Company’s recorded stock-based compensation expense: Three Months Ended June 30, Six Months Ended June 30, 2021 2020 2021 2020 (Dollars in thousands) (Dollars in thousands) Stock-based compensation expense $ 473 $ 406 $ 1,049 $ 832 Tax benefit 114 103 252 212 Stock-based compensation expense, net of tax $ 359 $ 303 $ 797 $ 620
Unearned Stock-based Compensation Expense	The Company will continue to amortize the unearned stock-based compensation expense over the remaining vesting period of approximately seven years. The following table shows the unearned stock-based compensation expense: June 30, 2021 (Dollars in thousands) Unearned stock-based compensation expense $ 5,417
Assumptions Used for Computing Stock-Based Compensation Expense	The following table shows the assumptions used for computing stock-based compensation expense under the fair value method on options granted during the periods presented: Six Months Ended June 30, 2021 2020 Weighted average grant-date fair value per share of options granted $ 23.74 $ 10.63 Risk-free interest rate 1.34 to 1.74% 0.66 to1.13% Dividend yield 2.00% 2.00% Stock price volatility 35.55 to 36.01% 22.84 to 33.56% Expected term 10 Yrs 10 Yrs
Summary of Accumulated Stock Units	A summary of the accumulated stock units is as follows: June 30, December 31, 2021 2020 Accumulated stock units 150,118 148,278 Average price $ 29.61 $ 28.57

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	6 Months Ended
	Jun. 30, 2021
Equity [Abstract]
Summary of Shares Repurchased Under Stock Purchase Program	The following table is a summary of the shares under the program: Six Months Ended June 30, 2021 2020 Number of shares repurchased — 59,284 Average price of shares repurchased $ — $ 52.26 Shares remaining to be repurchased 62,782 62,782
Required Capital Amounts and Company's Respective Ratios	The actual and required capital amounts and ratios are shown in the following table: Required To Be Well For Capital With Capitalized Under Adequacy Capital Conservation Prompt Corrective Actual Purposes Buffer Action Provisions Amount Ratio Amount Ratio Amount Ratio Amount Ratio (Dollars in thousands) As of June 30, 2021: Total Capital (to Risk Weighted Assets)- BancFirst Corporation $ 1,123,056 17.35% $ 517,721 8.00% $ 679,508 10.50% N/A N/A BancFirst 954,496 16.23% 470,400 8.00% 617,400 10.50% $ 588,000 10.00% Pegasus Bank 76,186 12.61% 48,317 8.00% 63,416 10.50% 60,396 10.00% Common Equity Tier 1 Capital (to Risk Weighted Assets)- BancFirst Corporation $ 956,969 14.79% $ 291,218 4.50% $ 453,006 7.00% N/A N/A BancFirst 860,924 14.64% 264,600 4.50% 411,600 7.00% $ 382,200 6.50% Pegasus Bank 71,113 11.77% 27,178 4.50% 42,277 7.00% 39,257 6.50% Tier 1 Capital (to Risk Weighted Assets)- BancFirst Corporation $ 982,969 15.19% $ 388,291 6.00% $ 550,078 8.50% N/A N/A BancFirst 880,924 14.98% 352,800 6.00% 499,800 8.50% $ 470,400 8.00% Pegasus Bank 71,113 11.77% 36,238 6.00% 51,337 8.50% 48,317 8.00% Tier 1 Capital (to Total Assets)- BancFirst Corporation $ 982,969 9.23% $ 425,962 4.00% N/A N/A N/A N/A BancFirst 880,924 9.13% 385,803 4.00% N/A N/A $ 482,254 5.00% Pegasus Bank 71,113 7.15% 39,786 4.00% N/A N/A 49,733 5.00%

Net Income Per Common Share (Ta

Net Income Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2021
Earnings Per Share [Abstract]
Basic and Diluted Net Income Per Common Share	Basic and diluted net income per common share are calculated as follows: Income (Numerator) Shares (Denominator) Per Share Amount (Dollars in thousands, except per share data) Three Months Ended June 30, 2021 Basic Income available to common stockholders $ 48,192 32,779,227 $ 1.47 Dilutive effect of stock options — 626,696 Diluted Income available to common stockholders plus assumed exercises of stock options $ 48,192 33,405,923 $ 1.45 Three Months Ended June 30, 2020 Basic Income available to common stockholders $ 20,730 32,651,262 $ 0.64 Dilutive effect of stock options — 424,231 Diluted Income available to common stockholders plus assumed exercises of stock options $ 20,730 33,075,493 $ 0.63 Six Months Ended June 30, 2021 Basic Income available to common stockholders $ 90,712 32,768,102 $ 2.77 Dilutive effect of stock options — 639,591 Diluted Income available to common stockholders plus assumed exercises of stock options $ 90,712 33,407,693 $ 2.72 Six Months Ended June 30, 2020 Basic Income available to common stockholders $ 43,338 32,665,425 $ 1.33 Dilutive effect of stock options — 531,996 Diluted Income available to common stockholders plus assumed exercises of stock options $ 43,338 33,197,421 $ 1.31
Average Exercise Price of Options Excluded from Computation of Diluted Net Income Per Common Share	The following table shows the number and average exercise price of options that were excluded from the computation of diluted net income per common share for each period because the options were anti-dilutive for the period: Shares Three Months Ended June 30, 2021 43,093 Three Months Ended June 30, 2020 448,016 Six Months Ended June 30, 2021 108,055 Six Months Ended June 30, 2020 424,939

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value of Financial Assets and Liabilities Measured on Recurring Basis	The following table summarizes financial assets and financial liabilities measured at fair value on a recurring basis as of the periods presented, segregated by the level of the valuation inputs within the fair value hierarchy utilized to measure fair value: Level 1 Inputs Level 2 Inputs Level 3 Inputs Total Fair Value (Dollars in thousands) June 30, 2021 Debt securities available for sale: U.S. Treasury $ 471,842 $ — $ — $ 471,842 U.S. federal agencies — 25,595 — 25,595 Mortgage-backed securities — 38,769 — 38,769 States and political subdivisions — 10,781 320 11,101 Asset backed securities — 13,476 — 13,476 December 31, 2020 Debt securities available for sale: U.S. Treasury $ 475,236 $ — $ — $ 475,236 U.S. federal agencies — 19,638 — 19,638 Mortgage-backed securities — 15,696 — 15,696 States and political subdivisions — 28,793 155 28,948 Asset backed securities — — 12,714 12,714
Changes in Level 3 Assets Measured at Estimated Fair Value on Recurring Basis	The changes in Level 3 assets measured at estimated fair value on a recurring basis during the periods presented were as follows: Six Months Ended June 30, Twelve Months Ended December 31, 2021 2020 (Dollars in thousands) Balance at the beginning of the year $ 12,869 $ 12,714 Transfers (to)/from level 2 (12,714 ) 1,643 Purchases 240 — Settlements (75 ) (1,473 ) Total unrealized losses — (15 ) Balance at the end of the period $ 320 $ 12,869
Assets Measured at Fair Value on Nonrecurring Basis	The following table summarizes assets measured at fair value on a nonrecurring basis during the period presented. The fair value represents end of period values, which approximate fair value measurements that occurred on various measurement dates throughout the period: Total Fair Value Level 3 (Dollars in thousands) As of and for the Year-to-date Period Ended June 30, 2021 Equity securities $ 21,548 Collateral dependent loans 867 Repossessed assets 50 Other real estate owned 8,009 As of and for the Year-to-date Period Ended December 31, 2020 Equity securities $ 21,203 Collateral dependent loans 11,347 Repossessed assets 291 Other real estate owned 32,066
Estimated Fair Values of Financial Instruments	The estimated fair values of the Company’s financial instruments that are reported at amortized cost in the Company’s consolidated balance sheets, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value, are as follows: June 30, December 31, 2021 2020 Carrying Amount Fair Value Carrying Amount Fair Value (Dollars in thousands) FINANCIAL ASSETS Level 2 inputs: Cash and cash equivalents $ 3,641,398 $ 3,641,398 $ 1,616,912 $ 1,616,912 Debt securities held for investment 43 45 59 62 Loans held for sale 16,032 16,032 53,719 53,719 Level 3 inputs: Debt securities held for investment 2,945 2,945 2,905 2,922 Loans, net of allowance for credit losses 6,107,267 6,108,907 6,303,140 6,347,803 FINANCIAL LIABILITIES Level 2 inputs: Deposits 9,728,389 9,817,785 8,064,704 8,084,695 Short-term borrowings 3,100 3,100 1,100 1,100 Subordinated debt 85,959 89,270 26,804 30,535 OFF-BALANCE SHEET FINANCIAL INSTRUMENTS Loan commitments 3,313 3,115 Letters of credit 567 722

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Results of Operations and Selected Financial Information	The results of operations and selected financial information for the five business units are as follows: Metropolitan Banks Community Banks Pegasus Bank Other Financial Services Executive, Operations & Support Eliminations Consolidated (Dollars in thousands) Three Months Ended June 30, 2021 Net interest income $ 19,848 $ 45,024 $ 5,808 $ 11,457 $ 9 $ 217 $ 82,363 Noninterest income 3,669 16,197 355 10,913 62,025 (48,541 ) 44,618 Income before taxes 17,602 36,514 1,947 5,220 49,790 (48,166 ) 62,907 Three Months Ended June 30, 2020 Net interest income $ 22,310 $ 43,917 $ 4,976 $ 5,905 $ 100 $ — $ 77,208 Noninterest income 4,571 13,841 121 9,328 25,774 (21,553 ) 32,082 Income before taxes 3,613 15,532 1,345 7,786 18,232 (21,202 ) 25,306 Six Months Ended June 30, 2021 Net interest income $ 39,181 $ 87,794 $ 11,167 $ 21,339 $ (398 ) $ 486 $ 159,569 Noninterest income 8,813 31,173 739 22,488 111,756 (90,416 ) 84,553 Income before taxes 31,526 66,283 3,592 11,171 92,130 (89,617 ) 115,085 Six Months Ended June 30, 2020 Net interest income $ 44,494 $ 88,415 $ 10,584 $ 7,488 $ 300 $ — $ 151,281 Noninterest income 9,271 29,694 252 20,218 53,257 (45,465 ) 67,227 Income before taxes 14,026 39,968 2,943 13,545 27,635 (44,561 ) 53,556 Total Assets: June 30, 2021 $ 3,247,686 $ 6,572,642 $ 966,809 $ 113,126 $ 1,437,732 $ (1,322,708 ) $ 11,015,287 December 31, 2020 2,729,886 5,527,611 919,572 137,122 1,073,507 (1,175,341 ) 9,212,357

Recent Developments, Includin_2

Recent Developments, Including Mergers and Acquisitions - Additional Information (Detail) $ in Thousands	Jun. 17, 2021USD ($)	May 20, 2021USD ($)Location	Jan. 22, 2021USD ($)	Jun. 30, 2021USD ($)	Dec. 31, 2020USD ($)
Business Combination Separately Recognized Transactions [Line Items]
Total assets				$ 11,015,287	$ 9,212,357
Loans held for investment (net of unearned interest)				6,191,230	6,394,506
Deposits				$ 9,728,389	$ 8,064,704
First National Bank and Trust [Member]
Business Combination Separately Recognized Transactions [Line Items]
Total assets		$ 284,000
Loans held for investment (net of unearned interest)		195,000
Deposits		256,000
Purchase price		21,000
Bargain purchase gain		6,000
Purchase expenses		4,000
Intangibles assets, net		$ 1,900
Subordinated Notes due 2036 [Member] | Private Placement [Member]
Business Combination Separately Recognized Transactions [Line Items]
Aggregate principal amount	$ 60,000
Fixed-to-floating rate	3.50%
Debt instrument maturity year	2036
Oklahoma [Member]
Business Combination Separately Recognized Transactions [Line Items]
Sale of Loans			$ 21,000
Deposits sold			38,000
Oklahoma [Member] | Noninterest Income [Member]
Business Combination Separately Recognized Transactions [Line Items]
Gain on transaction			$ 2,500
Oklahoma [Member] | First National Bank and Trust [Member]
Business Combination Separately Recognized Transactions [Line Items]
Number of banking locations | Location		2

Securities - Summary of Amortiz

Securities - Summary of Amortized Cost and Estimated Fair Values of Debt Securities Held for Investment (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	$ 2,988	$ 2,964
Gross Unrealized Gains	2	21
Gross Unrealized Losses		(1)
Estimated Fair Value	2,990	2,984
Mortgage Backed Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	43	59
Gross Unrealized Gains	2	3
Estimated Fair Value	45	62
States and Political Subdivisions [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	2,445	2,405
Gross Unrealized Gains		18
Gross Unrealized Losses		(1)
Estimated Fair Value	2,445	2,422
Other Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Amortized Cost	500	500
Estimated Fair Value	$ 500	$ 500

Securities - Summary of Amort_2

Securities - Summary of Amortized Cost and Estimated Fair Values of Debt Securities Available for Sale (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 553,662	$ 542,289
Gross Unrealized Gains	7,832	10,626
Gross Unrealized Losses	(711)	(683)
Estimated Fair Value	560,783	552,232
U.S. Treasuries [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	465,762	465,416
Gross Unrealized Gains	6,680	9,820
Gross Unrealized Losses	(600)
Estimated Fair Value	471,842	475,236
U.S. Federal Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	25,273	19,697
Gross Unrealized Gains	324	1
Gross Unrealized Losses	(2)	(60)
Estimated Fair Value	25,595	19,638
Mortgage Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	38,407	15,268
Gross Unrealized Gains	471	428
Gross Unrealized Losses	(109)
Estimated Fair Value	38,769	15,696
States and Political Subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	10,874	28,571
Gross Unrealized Gains	227	377
Estimated Fair Value	11,101	28,948
Asset backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	13,346	13,337
Gross Unrealized Gains	130
Gross Unrealized Losses		(623)
Estimated Fair Value	$ 13,476	$ 12,714

Securities - Maturity of Debt S

Securities - Maturity of Debt Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Held for Investment, Contractual maturity of debt securities, Amortized Cost
Amortized cost, Within one year	$ 576	$ 807
Amortized cost, After one year but within five years	2,407	2,091
Amortized cost, After five years but within ten years	4	65
Amortized cost, After ten years	1	1
Amortized Cost	2,988	2,964
Available for sale, Contractual maturity of debt securities, Amortized Cost
Amortized Cost, Within one year	110,293	339,752
Amortized Cost, After one year but within five years	373,494	162,401
Amortized Cost, After five years but within ten years	9,925	3,753
Amortized Cost, After ten years	59,950	36,383
Amortized Cost	553,662	542,289
Held for Investment, Contractual maturity of debt securities, Estimated Fair Value
Estimated Fair Value, Within one year	576	809
Estimated Fair Value, After one year but within five years	2,409	2,110
Estimated Fair Value, After five years but within ten years	4	64
Estimated Fair Value, After ten years	1	1
Estimated Fair Value	2,990	2,984
Available for sale, Contractual maturity of debt securities, Estimated Fair Value
Estimated Fair Value, Within one year	111,495	341,102
Estimated Fair Value, After one year but within five years	378,554	171,135
Estimated Fair Value, After five years but within ten years	10,467	3,910
Estimated Fair Value, After ten years	60,267	36,085
Total debt securities	$ 560,783	$ 552,232

Securities - Company's Book Val

Securities - Company's Book Value of Pledged Debt Securities (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Pledged Financial Instruments Not Separately Reported Securities Pledged By Type Of Security [Abstract]
Book value of pledged securities	$ 498,877	$ 490,833

Loans Held for Investment and_3

Loans Held for Investment and Allowance for Credit Losses on Loans - Summary of Loans Held for Investment by Portfolio Segment (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	$ 6,191,230	$ 6,394,506
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	661,530	641,987
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	989,560	971,158
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	297,205	229,615
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	208,210	206,195
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	865,557	853,316
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	163,290	168,081
Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	269,008	252,958
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	1,105,777	1,159,810
Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	371,557	355,405
Oil and Gas [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	130,459	179,355
Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	543,034	822,078
Pegasus Bank [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	586,043	$ 554,548
Pegasus Bank [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Loans (net of unearned interest)	$ 297,000

Loans Held for Investment and_4

Loans Held for Investment and Allowance for Credit Losses on Loans - Summary of Loans Held for Investment by Portfolio Segment (Parenthetical) (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Receivables [Abstract]
Accrued interest receivable	$ 22.9	$ 26
Pay check protection program loan held for investment	368.6	652.7
Paycheck protection program unamortized processing fees	$ 16.6	$ 14.5

Loans Held for Investment and_5

Loans Held for Investment and Allowance for Credit Losses on Loans - Additional Information (Detail) - USD ($)	Jan. 01, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	May 20, 2021
Financing Receivable Recorded Investment [Line Items]
Paycheck protection program amortized processing fees recognized as interest income		$ 21,700,000	$ 3,700,000	$ 11,900,000	$ 3,700,000
Total loans		6,191,230,000		6,191,230,000		$ 6,394,506,000
Gains (losses) on sale of property held in other real estate owned				(105,000)	2,300,000
Interest income that would have been recognized				1,200	983,000,000
Decrease in allowance for credit losses upon adoption of ASC 326	$ 3,200,000				3,195,000
Commercial Real Estate
Financing Receivable Recorded Investment [Line Items]
Loans modification		$ 61,800,000		61,800,000		81,700,000
U.S. Federal Agencies [Member]
Financing Receivable Recorded Investment [Line Items]
Nonaccrual loans guaranteed by government agencies				3,500,000		7,800,000
Previous Corporate Headquarters [Member] | Other Real Estate Owned [Member]
Financing Receivable Recorded Investment [Line Items]
Transferred premises and equipment to other real estate				2,400,000
First National Bank and Trust [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans							$ 195,000,000
First National Bank and Trust [Member] | Oklahoma [Member]
Financing Receivable Recorded Investment [Line Items]
Other real estate owned purchased				$ 2,500,000
BancFirst’s [Member]
Financing Receivable Recorded Investment [Line Items]
Percentage of loans secured by real estate		56.00%		56.00%
Pegasus Bank [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		$ 586,043,000		$ 586,043,000		554,548,000
Decrease in allowance for credit losses upon adoption of ASC 326					$ (2,488,000)
Pegasus Bank [Member] | Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Percentage of loans secured by real estate		51.00%		51.00%
Total loans		$ 297,000,000		$ 297,000,000
Pegasus Bank [Member] | Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans		$ 268,000,000		$ 268,000,000		$ 262,000,000

Loans Held for Investment and_6

Loans Held for Investment and Allowance for Credit Losses on Loans - Summary of Energy Loans (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable Recorded Investment [Line Items]
Total loans	$ 6,191,230	$ 6,394,506
Loans held for investment (net of unearned interest)	6,191,230	6,394,506
Pegasus Bank [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	586,043	554,548
Loans held for investment (net of unearned interest)	586,043	554,548
Energy [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	404,286	430,585
Loans held for investment (net of unearned interest)	404,286	430,585
Energy [Member] | BancFirst’s [Member] | Upstream Energy Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	141,651	190,788
Loans held for investment (net of unearned interest)	141,651	190,788
Energy [Member] | BancFirst’s [Member] | Midstream Energy Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	37,134	49,734
Loans held for investment (net of unearned interest)	37,134	49,734
Energy [Member] | BancFirst’s [Member] | Ancillary Services [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	74,919	59,410
Loans held for investment (net of unearned interest)	74,919	59,410
Energy [Member] | Pegasus Bank [Member] | Upstream Energy Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	127,736	107,103
Loans held for investment (net of unearned interest)	127,736	107,103
Energy [Member] | Pegasus Bank [Member] | Midstream Energy Loans [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	8,797	11,047
Loans held for investment (net of unearned interest)	8,797	11,047
Energy [Member] | Pegasus Bank [Member] | Ancillary Services [Member]
Financing Receivable Recorded Investment [Line Items]
Total loans	14,049	12,503
Loans held for investment (net of unearned interest)	$ 14,049	$ 12,503

Loans Held for Investment and_7

Loans Held for Investment and Allowance for Credit Losses on Loans - Summary of Troubled Debt Restructurings and Other Real Estate Owned and Repossessed Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Summary Of Nonperforming And Restructured Assets [Abstract]
Troubled debt restructurings	$ 7,485	$ 7,784
Other real estate owned and repossessed assets	$ 40,183	$ 32,480

Loans Held for Investment and_8

Loans Held for Investment and Allowance for Credit Losses on Loans - Summary of Amounts Included in Nonaccrual Loans Segregated by Portfolio Segment (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	$ 29,802	$ 37,545
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	2,572	1,404
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	422	4,719
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	88	95
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	3,518	3,615
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	1,188	1,362
Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	6,354	7,901
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	13,185	12,782
Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	188	268
Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual Loans, Total	$ 2,287	$ 5,399

Loans Held for Investment and_9

Loans Held for Investment and Allowance for Credit Losses on Loans - Age Analysis of Loans Held for Investments (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	$ 42,269	$ 45,532
Current Loans	6,148,961	6,348,974
Total Loans	6,191,230	6,394,506
Accruing Loans 90 Days or More Past Due	4,386	4,802
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,616	2,368
Current Loans	659,914	639,619
Total Loans	661,530	641,987
Accruing Loans 90 Days or More Past Due	80
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	317	357
Current Loans	989,243	970,801
Total Loans	989,560	971,158
Accruing Loans 90 Days or More Past Due	37	35
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,795	597
Current Loans	295,410	229,018
Total Loans	297,205	229,615
Accruing Loans 90 Days or More Past Due	137
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	103	1,388
Current Loans	208,107	204,807
Total Loans	208,210	206,195
Accruing Loans 90 Days or More Past Due		282
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	8,075	9,869
Current Loans	857,482	843,447
Total Loans	865,557	853,316
Accruing Loans 90 Days or More Past Due	2,070	945
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	2,771	2,181
Current Loans	160,519	165,900
Total Loans	163,290	168,081
Accruing Loans 90 Days or More Past Due	458	384
Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	6,352	7,864
Current Loans	262,656	245,094
Total Loans	269,008	252,958
Accruing Loans 90 Days or More Past Due	157	135
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	14,994	8,927
Current Loans	1,090,783	1,150,883
Total Loans	1,105,777	1,159,810
Accruing Loans 90 Days or More Past Due	638	465
Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	2,194	3,189
Current Loans	369,363	352,216
Total Loans	371,557	355,405
Accruing Loans 90 Days or More Past Due	190	386
Oil and Gas [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	130,459	179,355
Total Loans	130,459	179,355
Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	4,052	8,792
Current Loans	538,982	813,286
Total Loans	543,034	822,078
Accruing Loans 90 Days or More Past Due	619	2,170
Pegasus Bank [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	586,043	554,548
Total Loans	586,043	554,548
Pegasus Bank [Member] | Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Loans	297,000
30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	13,707	16,174
30 to 59 Days Past Due [Member] | Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	604	1,096
30 to 59 Days Past Due [Member] | Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	205	323
30 to 59 Days Past Due [Member] | Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	53	511
30 to 59 Days Past Due [Member] | Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	103	1,106
30 to 59 Days Past Due [Member] | Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	3,639	5,428
30 to 59 Days Past Due [Member] | Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,195	520
30 to 59 Days Past Due [Member] | Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,036	1,297
30 to 59 Days Past Due [Member] | Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	3,780	2,788
30 to 59 Days Past Due [Member] | Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,620	2,154
30 to 59 Days Past Due [Member] | Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,472	951
60 to 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	6,733	5,574
60 to 89 Days Past Due [Member] | Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans		108
60 to 89 Days Past Due [Member] | Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,605	86
60 to 89 Days Past Due [Member] | Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	447	1,463
60 to 89 Days Past Due [Member] | Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	40	55
60 to 89 Days Past Due [Member] | Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	989	344
60 to 89 Days Past Due [Member] | Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	2,821	1,794
60 to 89 Days Past Due [Member] | Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	353	501
60 to 89 Days Past Due [Member] | Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	478	1,223
90 Days and Greater [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	21,829	23,784
90 Days and Greater [Member] | Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,012	1,164
90 Days and Greater [Member] | Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	112	34
90 Days and Greater [Member] | Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	137
90 Days and Greater [Member] | Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans		282
90 Days and Greater [Member] | Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	3,989	2,978
90 Days and Greater [Member] | Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	1,536	1,606
90 Days and Greater [Member] | Real Estate [Member] | Farmland [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	4,327	6,223
90 Days and Greater [Member] | Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	8,393	4,345
90 Days and Greater [Member] | Consumer Non-real Estate [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	221	534
90 Days and Greater [Member] | Other Loans [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Total Past Due Loans	$ 2,102	$ 6,618

Loans Held for Investment an_10

Loans Held for Investment and Allowance for Credit Losses on Loans - Gross Loans Held for Investment by Year of Origination and Internally Assigned Credit Grades (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable Recorded Investment [Line Items]
2021	$ 1,538,093
2020	1,378,175
2019	900,281
2018	469,620
2017	358,467
Prior	789,747
Revolving Loans Amortized Cost Basis	756,847
Total Loans	6,191,230	$ 6,394,506
Pegasus Bank [Member]
Financing Receivable Recorded Investment [Line Items]
2021	91,154
2020	101,981
2019	76,339
2018	17,839
2017	37,580
Prior	59,149
Revolving Loans Amortized Cost Basis	202,001
Total Loans	586,043	554,548
Pegasus Bank [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	64,138
2020	87,556
2019	58,223
2018	7,261
2017	16,202
Prior	52,432
Revolving Loans Amortized Cost Basis	153,260
Total Loans	439,072
Pegasus Bank [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	27,016
2020	14,313
2019	18,116
2018	10,578
2017	21,378
Prior	6,717
Revolving Loans Amortized Cost Basis	48,741
Total Loans	146,859
Pegasus Bank [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2020	112
Total Loans	112
Real Estate [Member] | Pegasus Bank [Member]
Financing Receivable Recorded Investment [Line Items]
Total Loans	297,000
Real Estate [Member] | Farmland [Member]
Financing Receivable Recorded Investment [Line Items]
2021	38,174
2020	58,949
2019	53,242
2018	27,564
2017	20,478
Prior	50,251
Revolving Loans Amortized Cost Basis	20,350
Total Loans	269,008	252,958
Real Estate [Member] | Farmland [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	26,621
2020	46,638
2019	25,418
2018	18,375
2017	13,983
Prior	35,431
Revolving Loans Amortized Cost Basis	7,521
Total Loans	173,987
Real Estate [Member] | Farmland [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	8,767
2020	9,048
2019	26,148
2018	5,702
2017	5,457
Prior	13,424
Revolving Loans Amortized Cost Basis	10,709
Total Loans	79,255
Real Estate [Member] | Farmland [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	2,786
2020	2,068
2019	1,676
2018	300
2017	742
Prior	1,213
Revolving Loans Amortized Cost Basis	1,842
Total Loans	10,627
Real Estate [Member] | Farmland [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2020	1,195
2018	3,187
2017	296
Prior	183
Revolving Loans Amortized Cost Basis	278
Total Loans	5,139
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable Recorded Investment [Line Items]
2021	84,033
2020	177,604
2019	114,445
2018	65,059
2017	47,147
Prior	156,524
Revolving Loans Amortized Cost Basis	16,718
Total Loans	661,530	641,987
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	66,327
2020	135,671
2019	83,146
2018	53,559
2017	36,961
Prior	112,760
Revolving Loans Amortized Cost Basis	11,507
Total Loans	499,931
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	17,354
2020	38,028
2019	30,351
2018	10,695
2017	9,710
Prior	40,707
Revolving Loans Amortized Cost Basis	4,904
Total Loans	151,749
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	3
2020	3,905
2019	27
2018	266
2017	476
Prior	2,621
Total Loans	7,298
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	349
2019	921
2018	539
Prior	436
Revolving Loans Amortized Cost Basis	307
Total Loans	2,552
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable Recorded Investment [Line Items]
2021	119,058
2020	286,843
2019	195,492
2018	100,282
2017	82,366
Prior	182,838
Revolving Loans Amortized Cost Basis	22,681
Total Loans	989,560	971,158
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	95,260
2020	227,302
2019	147,192
2018	62,169
2017	61,402
Prior	137,491
Revolving Loans Amortized Cost Basis	18,024
Total Loans	748,840
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	16,345
2020	59,541
2019	44,838
2018	37,862
2017	19,357
Prior	43,884
Revolving Loans Amortized Cost Basis	4,657
Total Loans	226,484
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	7,453
2019	3,412
2018	214
2017	1,607
Prior	865
Total Loans	13,551
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2019	50
2018	37
Prior	598
Total Loans	685
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable Recorded Investment [Line Items]
2021	105,475
2020	77,646
2019	79,558
2018	13,583
2017	4,378
Prior	3,983
Revolving Loans Amortized Cost Basis	12,582
Total Loans	297,205	229,615
Real Estate [Member] | Construction and Development Less than 60 Months [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	91,143
2020	63,018
2019	66,976
2018	11,381
2017	2,547
Prior	3,210
Revolving Loans Amortized Cost Basis	10,454
Total Loans	248,729
Real Estate [Member] | Construction and Development Less than 60 Months [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	12,579
2020	12,938
2019	12,391
2018	2,187
2017	1,811
Prior	773
Revolving Loans Amortized Cost Basis	2,128
Total Loans	44,807
Real Estate [Member] | Construction and Development Less than 60 Months [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	1,753
2020	1,690
2019	130
2018	7
Total Loans	3,580
Real Estate [Member] | Construction and Development Less than 60 Months [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2019	61
2018	8
2017	20
Total Loans	89
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable Recorded Investment [Line Items]
2021	116,210
2020	84,088
2019	52
2018	109
2017	20
Prior	467
Revolving Loans Amortized Cost Basis	7,264
Total Loans	208,210	206,195
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	101,482
2020	69,169
2019	52
2017	20
Prior	30
Revolving Loans Amortized Cost Basis	7,264
Total Loans	178,017
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	14,182
2020	14,919
2018	109
Prior	437
Total Loans	29,647
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	546
Total Loans	546
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable Recorded Investment [Line Items]
2021	158,602
2020	215,971
2019	128,689
2018	91,194
2017	66,588
Prior	204,513
Total Loans	865,557	853,316
Real Estate [Member] | Residential Real Estate First Lien [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	134,782
2020	188,553
2019	109,336
2018	69,907
2017	54,107
Prior	154,974
Total Loans	711,659
Real Estate [Member] | Residential Real Estate First Lien [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	22,669
2020	25,098
2019	16,385
2018	19,237
2017	10,187
Prior	42,381
Total Loans	135,957
Real Estate [Member] | Residential Real Estate First Lien [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	1,102
2020	1,809
2019	2,526
2018	901
2017	1,360
Prior	4,832
Total Loans	12,530
Real Estate [Member] | Residential Real Estate First Lien [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	49
2020	511
2019	442
2018	1,149
2017	934
Prior	2,326
Total Loans	5,411
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable Recorded Investment [Line Items]
2021	10,879
2020	20,042
2019	13,292
2018	10,161
2017	7,027
Prior	18,671
Revolving Loans Amortized Cost Basis	83,218
Total Loans	163,290	168,081
Real Estate [Member] | Residential Real Estate All Other [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	9,847
2020	16,428
2019	11,139
2018	8,009
2017	5,157
Prior	15,276
Revolving Loans Amortized Cost Basis	28,321
Total Loans	94,177
Real Estate [Member] | Residential Real Estate All Other [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	746
2020	3,263
2019	1,743
2018	1,325
2017	1,137
Prior	2,367
Revolving Loans Amortized Cost Basis	53,510
Total Loans	64,091
Real Estate [Member] | Residential Real Estate All Other [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	272
2020	140
2019	410
2018	248
2017	718
Prior	376
Revolving Loans Amortized Cost Basis	1,042
Total Loans	3,206
Real Estate [Member] | Residential Real Estate All Other [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	14
2020	211
2018	579
2017	15
Prior	652
Revolving Loans Amortized Cost Basis	345
Total Loans	1,816
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
2021	234,753
2020	190,487
2019	138,512
2018	88,880
2017	61,121
Prior	75,793
Revolving Loans Amortized Cost Basis	316,231
Total Loans	1,105,777	1,159,810
Commercial and Agricultural Non-Real Estate [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	190,653
2020	135,726
2019	105,770
2018	64,491
2017	54,567
Prior	54,870
Revolving Loans Amortized Cost Basis	220,348
Total Loans	826,425
Commercial and Agricultural Non-Real Estate [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	38,938
2020	47,478
2019	29,481
2018	11,780
2017	3,885
Prior	18,985
Revolving Loans Amortized Cost Basis	68,353
Total Loans	218,900
Commercial and Agricultural Non-Real Estate [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	4,900
2020	5,500
2019	1,706
2018	12,010
2017	1,858
Prior	639
Revolving Loans Amortized Cost Basis	21,708
Total Loans	48,321
Commercial and Agricultural Non-Real Estate [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	262
2020	1,783
2019	1,555
2018	599
2017	811
Prior	1,299
Revolving Loans Amortized Cost Basis	5,822
Total Loans	12,131
Consumer Non-real Estate [Member]
Financing Receivable Recorded Investment [Line Items]
2021	119,776
2020	126,346
2019	70,593
2018	30,822
2017	10,769
Prior	5,873
Revolving Loans Amortized Cost Basis	7,378
Total Loans	371,557	355,405
Consumer Non-real Estate [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	110,171
2020	116,215
2019	64,985
2018	27,641
2017	9,497
Prior	4,018
Revolving Loans Amortized Cost Basis	7,084
Total Loans	339,611
Consumer Non-real Estate [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	9,362
2020	9,659
2019	4,641
2018	2,833
2017	1,099
Prior	1,653
Revolving Loans Amortized Cost Basis	287
Total Loans	29,534
Consumer Non-real Estate [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	229
2020	405
2019	787
2018	290
2017	154
Prior	147
Revolving Loans Amortized Cost Basis	3
Total Loans	2,015
Consumer Non-real Estate [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	14
2020	67
2019	180
2018	58
2017	19
Prior	55
Revolving Loans Amortized Cost Basis	4
Total Loans	397
Oil and Gas [Member]
Financing Receivable Recorded Investment [Line Items]
2021	80,264
2020	3,462
2019	128
2018	66
Prior	3,444
Revolving Loans Amortized Cost Basis	43,095
Total Loans	130,459	179,355
Oil and Gas [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	53,326
2020	115
2019	59
2018	66
Prior	3,444
Revolving Loans Amortized Cost Basis	33,676
Total Loans	90,686
Oil and Gas [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	10,051
2020	3,347
2019	69
Revolving Loans Amortized Cost Basis	9,419
Total Loans	22,886
Oil and Gas [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	16,887
Total Loans	16,887
Other Loans [Member]
Financing Receivable Recorded Investment [Line Items]
2021	379,715
2020	34,756
2019	29,939
2018	24,061
2017	20,993
Prior	28,241
Revolving Loans Amortized Cost Basis	25,329
Total Loans	543,034	$ 822,078
Other Loans [Member] | Grade 1 [Member]
Financing Receivable Recorded Investment [Line Items]
2021	379,715
2020	34,608
2019	29,464
2018	24,034
2017	18,060
Prior	25,568
Revolving Loans Amortized Cost Basis	23,298
Total Loans	534,747
Other Loans [Member] | Grade 2 [Member]
Financing Receivable Recorded Investment [Line Items]
2019	250
2018	17
2017	2,638
Prior	2,434
Revolving Loans Amortized Cost Basis	820
Total Loans	6,159
Other Loans [Member] | Grade 3 [Member]
Financing Receivable Recorded Investment [Line Items]
2020	11
2019	225
2018	10
2017	1
Prior	99
Revolving Loans Amortized Cost Basis	199
Total Loans	545
Other Loans [Member] | Grade 4 [Member]
Financing Receivable Recorded Investment [Line Items]
2020	137
2017	294
Prior	140
Revolving Loans Amortized Cost Basis	1,012
Total Loans	$ 1,583

Loans Held for Investment an_11

Loans Held for Investment and Allowance for Credit Losses on Loans - Activity in Allowance for Credit Losses on Loans (Detail) - USD ($) $ in Thousands	Jan. 01, 2020	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	$ 54,238	$ 90,860	$ 70,080	$ 91,366	$ 54,238
Impact of CECL adoption	(3,200)				(3,195)
Initial allowance on loans purchased with credit deterioration		7,272		7,272	502
Charge- offs		(4,448)	(462)	(5,114)	(1,622)
Recoveries		228	549	388	661
Net charge-offs		(4,220)	87	(4,726)	(961)
(Benefit from) provision for credit losses		(9,949)	19,333	(9,949)	38,916
Balance at end of period		83,963	89,500	83,963	89,500
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	5,625	6,595	4,544	7,035	5,625
Impact of CECL adoption					(2,806)
Initial allowance on loans purchased with credit deterioration		987		987	432
Charge- offs			(113)		(113)
Recoveries		1	1	1	1
Net charge-offs		1	(112)	1	(112)
(Benefit from) provision for credit losses		(828)	2,198	(1,268)	3,491
Balance at end of period		6,755	6,630	6,755	6,630
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	8,358	16,955	5,935	11,842	8,358
Impact of CECL adoption					(5,507)
Initial allowance on loans purchased with credit deterioration		633		633
Charge- offs		(758)		(796)
Net charge-offs		(758)		(796)
(Benefit from) provision for credit losses		(2,340)	3,548	2,811	6,632
Balance at end of period		14,490	9,483	14,490	9,483
Real Estate [Member] | Construction and Development Less than 60 Months [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	2,214	2,743	1,136	2,560	2,214
Impact of CECL adoption					(1,056)
Initial allowance on loans purchased with credit deterioration		173		173
Charge- offs			(56)		(59)
Recoveries		2	3	5	3
Net charge-offs		2	(53)	5	(56)
(Benefit from) provision for credit losses		(25)	672	155	653
Balance at end of period		2,893	1,755	2,893	1,755
Real Estate [Member] | Construction Residential Real Estate Less than 60 Months [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	1,933	983	1,618	627	1,933
Impact of CECL adoption					(778)
Charge- offs			(28)		(29)
Net charge-offs			(28)		(29)
(Benefit from) provision for credit losses		(94)	669	262	1,133
Balance at end of period		889	2,259	889	2,259
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	8,692	2,592	6,192	2,570	8,692
Impact of CECL adoption					(3,831)
Initial allowance on loans purchased with credit deterioration		117		117	7
Charge- offs		(9)	(66)	(52)	(218)
Recoveries		12	4	27	6
Net charge-offs		3	(62)	(25)	(212)
(Benefit from) provision for credit losses		93	2,423	143	3,897
Balance at end of period		2,805	8,553	2,805	8,553
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	2,767	1,873	2,292	2,230	2,767
Impact of CECL adoption					(1,408)
Charge- offs		(30)	(7)	(46)	(32)
Recoveries		1	1	4	28
Net charge-offs		(29)	(6)	(42)	(4)
(Benefit from) provision for credit losses		97	434	(247)	1,365
Balance at end of period		1,941	2,720	1,941	2,720
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	13,462	32,685	33,993	32,400	13,462
Impact of CECL adoption					13,195
Initial allowance on loans purchased with credit deterioration		4,711		4,711	62
Charge- offs		(3,433)	(287)	(3,537)	(374)
Recoveries		125	66	151	83
Net charge-offs		(3,308)	(221)	(3,386)	(291)
(Benefit from) provision for credit losses		(2,473)	264	(2,110)	7,608
Balance at end of period		31,615	34,036	31,615	34,036
Consumer Non-real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	3,252	3,256	3,385	3,377	3,252
Impact of CECL adoption					(622)
Initial allowance on loans purchased with credit deterioration		8		8
Charge- offs		(209)	(235)	(622)	(556)
Recoveries		86	57	198	114
Net charge-offs		(123)	(178)	(424)	(442)
(Benefit from) provision for credit losses		174	1,507	354	2,526
Balance at end of period		3,315	4,714	3,315	4,714
Oil and Gas [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	1,883	12,131	3,283	17,851	1,883
Impact of CECL adoption					(1,346)
(Benefit from) provision for credit losses		(4,314)	7,186	(10,034)	9,932
Balance at end of period		7,817	10,469	7,817	10,469
Other Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	2,632	3,190	2,751	3,182	2,632
Impact of CECL adoption					(116)
Charge- offs		(9)		(61)
Recoveries					2
Net charge-offs		(9)		(61)	2
(Benefit from) provision for credit losses		(43)	(238)	17	(5)
Balance at end of period		3,138	2,513	3,138	2,513
Farmland [Member] | Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	2,821	3,077	1,788	3,136	2,821
Impact of CECL adoption					(1,408)
Initial allowance on loans purchased with credit deterioration		643		643	1
Recoveries		1		1
Net charge-offs		1		1
(Benefit from) provision for credit losses		(6)	723	(65)	1,097
Balance at end of period		3,715	2,511	3,715	2,511
Pegasus Bank [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Balance at beginning of period	$ 599	4,780	3,163	4,556	599
Impact of CECL adoption					2,488
Charge- offs			330		(241)
Recoveries			417	1	424
Net charge-offs			747	1	183
(Benefit from) provision for credit losses		(190)	(53)	33	587
Balance at end of period		$ 4,590	$ 3,857	$ 4,590	$ 3,857

Loans Held for Investment an_12

Loans Held for Investment and Allowance for Credit Losses on Loans - Purchased Credit Deteriorated Loans (Detail) - Loans Acquired with Deteriorated Credit Quality [Member] - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Purchase price of loans at acquisition	$ 26,779	$ 1,761
Allowance for credit losses at acquisition	7,272	502
Par value of acquired loans at acquisition	$ 34,051	$ 2,263

Loans Held for Investment an_13

Loans Held for Investment and Allowance for Credit Losses on Loans - Collateral-dependent Gross Loans Held for Investment by Collateral Type and Related Specific Allocation (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	$ 15,752	$ 20,803
Pegasus Bank [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		1,257
Real Estate Asset [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	5,316	11,808
Real Estate Asset [Member] | Pegasus Bank [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		1,257
Business Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	5,226	8,473
Other Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	5,210	522
Specific Allocation [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	2,822	6,212
Specific Allocation [Member] | Pegasus Bank [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		222
Real Estate [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	645	848
Real Estate [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		4,719
Real Estate [Member] | Residential Real Estate First Lien [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	806	860
Real Estate [Member] | Residential Real Estate All Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	650	866
Real Estate [Member] | Farmland [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	3,215	3,258
Real Estate [Member] | Real Estate Asset [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	645	848
Real Estate [Member] | Real Estate Asset [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		4,719
Real Estate [Member] | Real Estate Asset [Member] | Residential Real Estate First Lien [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	806	860
Real Estate [Member] | Real Estate Asset [Member] | Residential Real Estate All Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	650	866
Real Estate [Member] | Real Estate Asset [Member] | Farmland [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	3,215	3,258
Real Estate [Member] | Specific Allocation [Member] | Commercial Real Estate Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	176	226
Real Estate [Member] | Specific Allocation [Member] | Commercial Real Estate Non-Owner Occupied [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans		1,000
Real Estate [Member] | Specific Allocation [Member] | Residential Real Estate First Lien [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	158	151
Real Estate [Member] | Specific Allocation [Member] | Residential Real Estate All Other [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	568	616
Real Estate [Member] | Specific Allocation [Member] | Farmland [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	1,123	1,114
Commercial and Agricultural Non-Real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	10,399	8,873
Commercial and Agricultural Non-Real Estate [Member] | Business Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	5,211	8,460
Commercial and Agricultural Non-Real Estate [Member] | Other Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	5,188	413
Commercial and Agricultural Non-Real Estate [Member] | Specific Allocation [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	778	2,813
Consumer Non-real Estate [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	22	109
Consumer Non-real Estate [Member] | Other Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	22	109
Consumer Non-real Estate [Member] | Specific Allocation [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	4	58
Other Loans [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	15	13
Other Loans [Member] | Business Assets [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	15	13
Other Loans [Member] | Specific Allocation [Member]
Financing Receivable Allowance For Credit Losses [Line Items]
Collateral Dependent Loans	$ 15	$ 12

Loans Held for Investment an_14

Loans Held for Investment and Allowance for Credit Losses on Loans - Transfers from Loans and Premises and Equipment to Other Real Estate Owned and Repossessed Assets (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Noncash Investing And Financing Items [Abstract]
Other real estate owned	$ 9,438	$ 2,876
Repossessed assets	427	722
Total	$ 9,865	$ 3,598

Intangible Assets and Goodwil_2

Intangible Assets and Goodwill - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 34,199	$ 36,761
Accumulated Amortization	(14,916)	(17,762)
Net Carrying Amount	19,283	18,999
Core Deposit Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	30,849	33,411
Accumulated Amortization	(12,120)	(15,076)
Net Carrying Amount	18,729	18,335
Customer Relationship Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,350	3,350
Accumulated Amortization	(2,796)	(2,686)
Net Carrying Amount	$ 554	$ 664

Intangible Assets and Goodwil_3

Intangible Assets and Goodwill - Summary of Goodwill by Business Segment (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Goodwill [Line Items]
Goodwill	$ 149,922	$ 149,922
Metropolitan Banks [Member]
Goodwill [Line Items]
Goodwill	13,767
Community Banks [Member]
Goodwill [Line Items]
Goodwill	61,212
Pegasus Bank [Member]
Goodwill [Line Items]
Goodwill	68,855
Other Financial Services [Member]
Goodwill [Line Items]
Goodwill	5,464
Executive, Operations & Support [Member]
Goodwill [Line Items]
Goodwill	$ 624

Leases - Additional Information

Leases - Additional Information (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Leases [Abstract]
Rent expense for operating leases	$ 462,000	$ 453,000	$ 966,000	$ 916,000
Right of use lease asset	$ 3,800,000		$ 3,800,000
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	banf:AccruedInterestReceivableAndOtherAssetsMember		banf:AccruedInterestReceivableAndOtherAssetsMember
Operating lease liability	$ 3,650,000		$ 3,650,000
Operating Lease, Liability, Statement of Financial Position [Extensible List]	banf:AccruedInterestPayableAndOtherLiabilitiesMember		banf:AccruedInterestPayableAndOtherLiabilitiesMember
Operating lease weighted-average remaining lease term	3 years 3 months 18 days		3 years 3 months 18 days
Operating lease weighted-average discount rate	2.80%		2.80%
Operating lease revenue	$ 1,300,000	$ 1,400,000	$ 2,700,000	$ 2,800,000

Leases - Schedule of Minimum Fu

Leases - Schedule of Minimum Future Commitments of Operating Leases (Detail) $ in Thousands	Jun. 30, 2021USD ($)
Leases [Abstract]
2021 (six months)	$ 703
2022	1,212
2023	708
2024	345
2025	286
Thereafter	893
Total lease payments	4,147
Less imputed Interest	(497)
Operating lease liability	$ 3,650

Leases - Scheduled of Minimum F

Leases - Scheduled of Minimum Future Contractual Rent To be Received Under The Remaining Non-Cancelable Term of Operating Leases (Detail) $ in Thousands	Jun. 30, 2021USD ($)
Leases [Abstract]
2021 (six months)	$ 1,765
2022	2,857
2023	2,636
2024	2,571
2025	1,946
2026-2031	6,146
Total future minimum lease payments	$ 17,921

Subordinated Debt - Additional

Subordinated Debt - Additional Information (Detail) - USD ($)	Jun. 17, 2021	Mar. 31, 2004	Feb. 29, 2004	Jun. 30, 2021
Subordinated Notes due 2036 [Member] | Private Placement [Member]
Subordinated Borrowing [Line Items]
Interest rate of securities	3.50%
Debt instrument maturity date				Jun. 30, 2036
Aggregate principal amount	$ 60,000,000
Net proceeds from sale of notes	59,150,000
Commissions and offering expenses	$ 850,000
Debt instrument, redemption, description				the Company may redeem all, but not less than all, of the Subordinated Notes at any time upon the occurrence of a “Tier 2 Capital Event,” a “Tax Event” or an “Investment Company Event” (each as defined in the Subordinated Notes). Any such redemption is subject to obtaining the prior approval of the Board of Governors of the Federal Reserve System (or its designee). The redemption price with respect to any such redemption will be equal to 100% of the principal amount of the Subordinated Note, or portion thereof, to be redeemed, plus accrued but unpaid interest, if any, thereon to, but excluding, the redemption date.
Debt instrument, redemption price, percentage of principal amount redeemed				100.00%
Subordinated Notes due 2036 [Member] | Private Placement [Member] | Bear Interest at Fixed Rate of 3.50% [Member]
Subordinated Borrowing [Line Items]
Frequency of payment				payable semi-annually in arrears on June 30 and December 31 of each year
Debt instrument, payment terms				The Subordinated Notes will initially bear interest at a fixed rate of 3.50% per annum, from and including June 17, 2021 to but excluding June 30, 2031, payable semi-annually in arrears on June 30 and December 31 of each year, commencing December 31, 2021. Then, from and including June 30, 2031, to but excluding the maturity date, the Subordinated Notes will bear interest at a floating rate equal to the benchmark (initially, three-month term SOFR), reset quarterly, plus a spread of 229 basis points, payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year. The Subordinated Notes mature on June 30, 2036.
Fixed rate				3.50%
Debt instrument, commencing date				Dec. 31, 2021
Subordinated Notes due 2036 [Member] | Private Placement [Member] | Three-Month Term SOFR [Member]
Subordinated Borrowing [Line Items]
Frequency of payment				payable quarterly in arrears on March 31, June 30, September 30 and December 31 of each year.
Debt instrument, Basis point rate				2.29%
BancFirst Capital Trust Two [Member] | Subordinated Debentures Subject to Mandatory Redemption [Member]
Subordinated Borrowing [Line Items]
Junior subordinated notes assumed				$ 26,800,000
Interest rate of securities				7.20%
Frequency of payment				payable January 15, April 15, July 15 and October 15 of each year.
Debt instrument maturity date				Mar. 31, 2034
BancFirst Capital Trust Two [Member] | Cumulative Preferred Stock [Member]
Subordinated Borrowing [Line Items]
Issue of securities		$ 1,000,000	$ 25,000,000
Cumulative trust preferred securities interest rate				7.20%

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash settlement for stock options, number of shares	121,330
Net cash settlement for stock options, cost	$ 5.5
Deferred board fees percentage for stock units accumulation	100.00%
Nonqualified Incentive Stock Option Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period in years	7 years
Nonqualified Incentive Stock Option Plan [Member] | Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares for future grants	275,000
Stock option plan termination date	Dec. 31, 2024
Option exercisable rate	25.00%
Option exercisable period	4 years
Options expire period	15 years
Vesting period in years, start	4 years
Options vest and exercisable Description	The options vest and are exercisable beginning four years from the date of grant at the rate of 25% per year for four years. Options expire no later than the end of fifteen years from the date of grant
Nonqualified Incentive Stock Option Plan [Member] | Stock Option [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock price percentage to fair value at grant date	100.00%
Non-Employee Directors Stock Option Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares for future grants	50,000
Stock option plan termination date	Dec. 31, 2024
Option exercisable rate	25.00%
Option exercisable period	1 year
Options expire period	15 years
Options vest and exercisable Description	The options vest and are exercisable beginning one year from the date of grant at the rate of 25% per year for four years
Number of options granted for non-employee director	10,000
Vesting period in years	4 years
Non-Employee Directors Stock Option Plan [Member] | Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock price percentage to fair value at grant date	100.00%
Banc First Deferred Stock Compensation Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option plan termination date	Dec. 31, 2024
Number of shares available for future issuance under deferred compensation plan	40,000
Number of shares of common stock distributed	2,161	1,307

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Activity Under Stock Option Plan (Detail) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2021USD ($)$ / sharesshares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding at beginning period - Options | shares	1,343,080
Options granted | shares	53,000
Options exercised | shares	(183,830)
Options canceled, forfeited, or expired | shares	(5,000)
Outstanding at ending period - Options | shares	1,207,250
Exercisable at ending period - Options | shares	596,750
Outstanding at beginning period - Wgtd. Avg. Exercise Price | $ / shares	$ 35.28
Options granted - Wgtd. Avg. Exercise Price | $ / shares	69.57
Options exercised - Wgtd. Avg. Exercise Price | $ / shares	23.82
Options cancelled, forfeited, or expired - Wgtd. Avg. Exercise Price | $ / shares	44.23
Outstanding at ending period - Wgtd. Avg. Exercise Price | $ / shares	38.49
Exercisable at ending period - Wgtd. Avg. Exercise Price | $ / shares	$ 26.68
Outstanding at ending period - Wgtd. Avg. Remaining Contractual Term, years	8 years 10 months 20 days
Exercisable at ending period - Wgtd. Avg. Remaining Contractual Term, years	7 years 3 months 29 days
Outstanding at ending period - Aggregate Intrinsic Value | $	$ 28,896
Exercisable at ending period - Aggregate Intrinsic Value | $	$ 21,336

Stock-Based Compensation - Opti

Stock-Based Compensation - Options Exercised Under Stock Option Plan (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award Options Additional Disclosures [Abstract]
Total intrinsic value of options exercised	$ 557	$ 337	$ 7,860	$ 726
Cash received from options exercised	413	303	4,379	504
Tax benefit realized from options exercised	$ 142	$ 86	$ 2,002	$ 185

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock-Based Employee Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Labor And Related Expense [Abstract]
Stock-based compensation expense	$ 473	$ 406	$ 1,049	$ 832
Tax benefit	114	103	252	212
Stock-based compensation expense, net of tax	$ 359	$ 303	$ 797	$ 620

Stock-Based Compensation - Unea

Stock-Based Compensation - Unearned Stock-based Compensation Expense (Detail) $ in Thousands	Jun. 30, 2021USD ($)
Share Based Compensation [Abstract]
Unearned stock-based compensation expense	$ 5,417

Stock-Based Compensation - Assu

Stock-Based Compensation - Assumptions Used for Computing Stock-Based Compensation Expense (Detail) - $ / shares	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Abstract]
Weighted average grant-date fair value per share of options granted	$ 23.74	$ 10.63
Risk-free interest rate, minimum	1.34%	0.66%
Risk-free interest rate, maximum	1.74%	1.13%
Dividend yield	2.00%	2.00%
Stock price volatility, minimum	35.55%	22.84%
Stock price volatility, maximum	36.01%	33.56%
Expected term	10 years	10 years

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Accumulated Stock Units (Detail) - $ / shares	Jun. 30, 2021	Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Accumulated stock units	150,118	148,278
Average price	$ 29.61	$ 28.57

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Shares Repurchased Under Stock Purchase Program (Detail) - $ / shares	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2021
Summary Of Shares Repurchased Under Stock Purchase Program [Abstract]
Number of shares repurchased	59,284
Average price of shares repurchased	$ 52.26
Shares remaining to be repurchased	62,782	62,782

Stockholders' Equity - Required

Stockholders' Equity - Required Capital Amounts and Company's Respective Ratios (Detail) $ in Thousands	Jun. 30, 2021USD ($)
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 1,123,056
Total Capital To Risk Weighted Assets Actual Ratio	17.35
Capital Required For Capital Adequacy Amount	$ 517,721
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	8
Capital With Capital Conservation Buffer Amount	$ 679,508
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	10.50
Common Equity Tier 1 Risk Based Capital Amount	$ 956,969
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	14.79
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 291,218
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	4.50
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 453,006
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	7
Tier 1 Risk Based Capital Amount	$ 982,969
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	15.19
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 388,291
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	6
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 550,078
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	8.50
Tier 1 Capital Amount	$ 982,969
Tier 1 Capital To Average Assets Ratio	9.23
Tier 1 Capital Required For Capital Adequacy Amount	$ 425,962
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	4
BancFirst [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 954,496
Total Capital To Risk Weighted Assets Actual Ratio	16.23
Capital Required For Capital Adequacy Amount	$ 470,400
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	8
Capital With Capital Conservation Buffer Amount	$ 617,400
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	10.50
Capital Required To Be Well Capitalized Amount	$ 588,000
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	10
Common Equity Tier 1 Risk Based Capital Amount	$ 860,924
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	14.64
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 264,600
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	4.50
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 411,600
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	7
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 382,200
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	6.50
Tier 1 Risk Based Capital Amount	$ 880,924
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	14.98
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 352,800
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	6
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 499,800
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	8.50
Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 470,400
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	8
Tier 1 Capital Amount	$ 880,924
Tier 1 Capital To Average Assets Ratio	9.13
Tier 1 Capital Required For Capital Adequacy Amount	$ 385,803
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	4
Tier 1 Capital Required To Be Well Capitalized Amount	$ 482,254
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio	5
Pegasus Bank [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 76,186
Total Capital To Risk Weighted Assets Actual Ratio	12.61
Capital Required For Capital Adequacy Amount	$ 48,317
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	8
Capital With Capital Conservation Buffer Amount	$ 63,416
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	10.50
Capital Required To Be Well Capitalized Amount	$ 60,396
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	10
Common Equity Tier 1 Risk Based Capital Amount	$ 71,113
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	11.77
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 27,178
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	4.50
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 42,277
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	7
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 39,257
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	6.50
Tier 1 Risk Based Capital Amount	$ 71,113
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	11.77
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 36,238
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	6
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 51,337
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	8.50
Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 48,317
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	8
Tier 1 Capital Amount	$ 71,113
Tier 1 Capital To Average Assets Ratio	7.15
Tier 1 Capital Required For Capital Adequacy Amount	$ 39,786
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	4
Tier 1 Capital Required To Be Well Capitalized Amount	$ 49,733
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio	5

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	Jun. 30, 2021	Jun. 17, 2021
Subordinated Notes due 2036 [Member] | Private Placement [Member]
Stockholders Equity [Line Items]
Aggregate principal amount		$ 60,000,000
Small Business Administration (SBA), CARES Act, Paycheck Protection Program Lending Facility [Member]
Stockholders Equity [Line Items]
Percentage of risk weight under risk based capital rules	0.00%
Maximum [Member]
Stockholders Equity [Line Items]
Quantitative limit for trust preferred securities to be included in tier 1 capital	$ 15,000,000,000

Net Income Per Common Share - B

Net Income Per Common Share - Basic and Diluted Net Income Per Common Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share Reconciliation [Abstract]
Income available to common stockholders	$ 48,192	$ 20,730	$ 90,712	$ 43,338
Income available to common stockholders plus assumed exercises of stock options	$ 48,192	$ 20,730	$ 90,712	$ 43,338
Income available to common stockholders - Shares	32,779,227	32,651,262	32,768,102	32,665,425
Dilutive effect of stock options - Shares	626,696	424,231	639,591	531,996
Income available to common stockholders plus assumed exercises of stock options - Shares	33,405,923	33,075,493	33,407,693	33,197,421
Income available to common stockholders - Per Share Amount	$ 1.47	$ 0.64	$ 2.77	$ 1.33
Income available to common stockholders plus assumed exercises of stock options - Per Share Amount	$ 1.45	$ 0.63	$ 2.72	$ 1.31

Net Income Per Common Share - A

Net Income Per Common Share - Average Exercise Prices of Options Excluded from Computation of Diluted Net Income Per Common Share (Detail) - shares	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Abstract]
Shares	43,093	448,016	108,055	424,939

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	$ 560,783	$ 552,232
U.S. Treasury [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	471,842	475,236
U.S. Federal Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	25,595	19,638
Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	38,769	15,696
States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	11,101	28,948
Asset backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	13,476	12,714
Level 1 Inputs [Member] | U.S. Treasury [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	471,842	475,236
Level 2 Inputs [Member] | U.S. Federal Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	25,595	19,638
Level 2 Inputs [Member] | Mortgage Backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	38,769	15,696
Level 2 Inputs [Member] | States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	10,781	28,793
Level 2 Inputs [Member] | Asset backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	13,476
Level 3 Inputs [Member] | States and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale	$ 320	155
Level 3 Inputs [Member] | Asset backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt securities available for sale		$ 12,714

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Level 3 Assets Measured at Estimated Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation Calculation Roll Forward
Balance at the beginning of the year	$ 12,869	$ 12,714
Transfers (to)/from level 2	(12,714)	1,643
Purchases	240
Settlements	(75)	(1,473)
Total unrealized losses		(15)
Balance at the end of the period	$ 320	$ 12,869

Fair Value Measurements - Asset

Fair Value Measurements - Assets Measured at Fair Value on Nonrecurring Basis (Detail) - Level 3 [Member] - Nonrecurring [Member] - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Equity Securities [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 21,548	$ 21,203
Repossessed Assets [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	50	291
Collateral Dependent Loans
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	867	11,347
Other Real Estate Owned [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Total Fair Value	$ 8,009	$ 32,066

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Days from origination after which mortgage loans are sold	30 days
Amount of non-financial assets (liabilities) measured at fair value on a recurring basis	$ 0	$ 0
Non-financial assets or liabilities for which no impairment was provided	0	0
Level 2 Inputs [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans held for sale	$ 16,032,000	53,719,000
Level 2 Inputs [Member] | BancFirst [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Loans held for sale		$ 21,600,000

Fair Value Measurements - Estim

Fair Value Measurements - Estimated Fair Values of Company's Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
FINANCIAL ASSETS
Debt securities held for investment (fair value: $2,990 and $2,984, respectively)	$ 2,988	$ 2,964
Loans, net of allowance for credit losses, Carrying Amount	6,107,267	6,303,140
Debt securities held for investment, Fair Value	2,990	2,984
Loans held for sale, Fair Value	16,032	53,719
FINANCIAL LIABILITIES
Deposits, Carrying Amount	9,728,389	8,064,704
Short-term borrowings, Carrying Amount	3,100	1,100
Subordinated debt, Carrying Amount	85,959	26,804
OFF-BALANCE SHEET FINANCIAL INSTRUMENTS
Loan commitments, Fair Value	3,313	3,115
Letters of credit, Fair Value	567	722
Level 2 Inputs [Member]
FINANCIAL ASSETS
Cash and cash equivalents, Carrying Amount	3,641,398	1,616,912
Debt securities held for investment (fair value: $2,990 and $2,984, respectively)	43	59
Loans held for sale, Carrying Amount	16,032	53,719
Cash and cash equivalents, Fair Value	3,641,398	1,616,912
Debt securities held for investment, Fair Value	45	62
Loans held for sale, Fair Value	16,032	53,719
FINANCIAL LIABILITIES
Deposits, Carrying Amount	9,728,389	8,064,704
Short-term borrowings, Carrying Amount	3,100	1,100
Subordinated debt, Carrying Amount	85,959	26,804
Deposits, Fair Value	9,817,785	8,084,695
Short-term borrowings, Fair Value	3,100	1,100
Subordinated debt, Fair Value	89,270	30,535
Level 3 Inputs [Member]
FINANCIAL ASSETS
Debt securities held for investment (fair value: $2,990 and $2,984, respectively)	2,945	2,905
Loans, net of allowance for credit losses, Carrying Amount	6,107,267	6,303,140
Debt securities held for investment, Fair Value	2,945	2,922
Loans, net of allowance for credit losses, Fair Value	$ 6,108,907	$ 6,347,803

Segment Information - Additiona

Segment Information - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2021Business_Unit
Segment Reporting [Abstract]
Number of principal business units	5

Segment Information - Results o

Segment Information - Results of Operations and Selected Financial Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Net interest income	$ 82,363	$ 77,208	$ 159,569	$ 151,281
Noninterest income	44,618	32,082	84,553	67,227
Income before taxes	62,907	25,306	115,085	53,556
Total assets	11,015,287		11,015,287		$ 9,212,357
Operating Segments [Member] | Metropolitan Banks [Member]
Segment Reporting Information [Line Items]
Net interest income	19,848	22,310	39,181	44,494
Noninterest income	3,669	4,571	8,813	9,271
Income before taxes	17,602	3,613	31,526	14,026
Total assets	3,247,686		3,247,686		2,729,886
Operating Segments [Member] | Community Banks [Member]
Segment Reporting Information [Line Items]
Net interest income	45,024	43,917	87,794	88,415
Noninterest income	16,197	13,841	31,173	29,694
Income before taxes	36,514	15,532	66,283	39,968
Total assets	6,572,642		6,572,642		5,527,611
Operating Segments [Member] | Pegasus Bank [Member]
Segment Reporting Information [Line Items]
Net interest income	5,808	4,976	11,167	10,584
Noninterest income	355	121	739	252
Income before taxes	1,947	1,345	3,592	2,943
Total assets	966,809		966,809		919,572
Operating Segments [Member] | Other Financial Services [Member]
Segment Reporting Information [Line Items]
Net interest income	11,457	5,905	21,339	7,488
Noninterest income	10,913	9,328	22,488	20,218
Income before taxes	5,220	7,786	11,171	13,545
Total assets	113,126		113,126		137,122
Operating Segments [Member] | Executive, Operations & Support [Member]
Segment Reporting Information [Line Items]
Net interest income	9	100	(398)	300
Noninterest income	62,025	25,774	111,756	53,257
Income before taxes	49,790	18,232	92,130	27,635
Total assets	1,437,732		1,437,732		1,073,507
Eliminations [Member]
Segment Reporting Information [Line Items]
Net interest income	217		486
Noninterest income	(48,541)	(21,553)	(90,416)	(45,465)
Income before taxes	(48,166)	$ (21,202)	(89,617)	$ (44,561)
Total assets	$ (1,322,708)		$ (1,322,708)		$ (1,175,341)