Stockholders' Equity - Required Capital Amounts and Company's Respective Ratios (Detail) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Parent Company [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 1,298,329	$ 1,171,215
Total Capital To Risk Weighted Assets Actual Ratio	0.1661	0.1730
Capital Required For Capital Adequacy Amount	$ 625,387	$ 541,493
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	0.0800	0.0800
Capital With Capital Conservation Buffer Amount	$ 820,821	$ 710,709
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	0.1050	0.1050
Common Equity Tier 1 Risk Based Capital Amount	$ 1,120,361	$ 1,002,096
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1433	0.1480
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 351,780	$ 304,590
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0450	0.0450
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 547,214	$ 473,806
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0700	0.0700
Tier 1 Risk Based Capital Amount	$ 1,146,361	$ 1,028,096
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1466	0.1519
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 469,041	$ 406,120
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0600	0.0600
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 664,474	$ 575,336
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0850	0.0850
Tier 1 Capital Amount	$ 1,146,361	$ 1,028,096
Tier 1 Capital To Average Assets Ratio	0.0930	0.0914
Tier 1 Capital Required For Capital Adequacy Amount	$ 493,191	$ 449,847
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	0.0400	0.0400
BancFirst [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 1,092,098	$ 1,004,835
Total Capital To Risk Weighted Assets Actual Ratio	0.1668	0.1675
Capital Required For Capital Adequacy Amount	$ 523,932	$ 479,883
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	0.0800	0.0800
Capital With Capital Conservation Buffer Amount	$ 687,661	$ 629,847
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	0.1050	0.1050
Capital Required To Be Well Capitalized Amount	$ 654,916	$ 599,854
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.1000	0.1000
Common Equity Tier 1 Risk Based Capital Amount	$ 991,050	$ 909,817
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1513	0.1517
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 294,712	$ 269,934
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0450	0.0450
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 458,441	$ 419,898
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0700	0.0700
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 425,695	$ 389,905
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0650	0.0650
Tier 1 Risk Based Capital Amount	$ 1,011,050	$ 929,817
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1544	0.1550
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 392,949	$ 359,913
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0600	0.0600
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 556,678	$ 509,876
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0850	0.0850
Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 523,932	$ 479,883
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0800	0.0800
Tier 1 Capital Amount	$ 1,011,050	$ 929,817
Tier 1 Capital To Average Assets Ratio	0.0972	0.0922
Tier 1 Capital Required For Capital Adequacy Amount	$ 416,004	$ 403,460
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	0.0400	0.0400
Tier 1 Capital Required To Be Well Capitalized Amount	$ 520,005	$ 504,325
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio	0.0500	0.0500
Pegasus [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 117,445	$ 88,224
Total Capital To Risk Weighted Assets Actual Ratio	0.1291	0.1162
Capital Required For Capital Adequacy Amount	$ 77,802	$ 60,765
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	0.0800	0.0800
Capital With Capital Conservation Buffer Amount	$ 95,553	$ 79,754
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	0.1050	0.1050
Capital Required To Be Well Capitalized Amount	$ 91,003	$ 75,956
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.1000	0.1000
Common Equity Tier 1 Risk Based Capital Amount	$ 108,437	$ 82,056
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1192	0.1080
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 40,951	$ 34,180
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0450	0.0450
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 63,702	$ 53,170
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0700	0.0700
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 59,152	$ 49,372
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0650	0.0650
Tier 1 Risk Based Capital Amount	$ 108,437	$ 82,056
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1192	0.1080
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 54,602	$ 45,574
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0600	0.0600
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 77,352	$ 64,563
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0850	0.0850
Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 72,802	$ 60,765
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0800	0.0800
Tier 1 Capital Amount	$ 108,437	$ 82,056
Tier 1 Capital To Average Assets Ratio	0.0800	0.0698
Tier 1 Capital Required For Capital Adequacy Amount	$ 54,238	$ 47,054
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	0.0400	0.0400
Tier 1 Capital Required To Be Well Capitalized Amount	$ 67,798	$ 58,817
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio	0.0500	0.0500
Worthington [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Total Capital Amount	$ 47,554
Total Capital To Risk Weighted Assets Actual Ratio	0.1409
Capital Required For Capital Adequacy Amount	$ 27,006
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	0.0800
Capital With Capital Conservation Buffer Amount	$ 35,446
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio	0.1050
Capital Required To Be Well Capitalized Amount	$ 33,758
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.1000
Common Equity Tier 1 Risk Based Capital Amount	$ 44,207
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1310
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 15,191
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0450
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 23,631
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0700
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 21,943
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0650
Tier 1 Risk Based Capital Amount	$ 44,207
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	0.1310
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	$ 20,255
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	0.0600
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount	$ 28,694
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio	0.0850
Tier 1 Risk Based Capital Required To Be Well Capitalized Amount	$ 27,006
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	0.0800
Tier 1 Capital Amount	$ 44,207
Tier 1 Capital To Average Assets Ratio	0.0853
Tier 1 Capital Required For Capital Adequacy Amount	$ 20,738
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	0.0400
Tier 1 Capital Required To Be Well Capitalized Amount	$ 25,922
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio	0.0500