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Stockholders' Equity - Required Capital Amounts and Company's Respective Ratios (Detail) $ in Thousands | Mar. 31, 2021 USD ($)
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Parent Company [Member] |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Total Capital Amount | $ 1,024,295
Total Capital To Risk Weighted Assets Actual Ratio | 16.41
Capital Required For Capital Adequacy Amount | $ 499,314
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio | 8.00
Capital With Capital Conservation Buffer Amount | $ 655,350
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio | 10.50
Common Equity Tier 1 Risk Based Capital Amount | $ 920,119
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 14.74
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 280,864
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 | $ 436,900
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio | 7.00
Tier 1 Risk Based Capital Amount | $ 946,119
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 15.16
Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 374,486
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio | 6.00
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount | $ 530,521
Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio | 8.50
Tier 1 Capital Amount | $ 946,119
Tier 1 Capital To Average Assets Ratio | 9.45
Tier 1 Capital Required For Capital Adequacy Amount | $ 400,544
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio | 4.00
BancFirst [Member] |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Total Capital Amount | $ 919,705
Total Capital To Risk Weighted Assets Actual Ratio | 16.27
Capital Required For Capital Adequacy Amount | $ 452,334
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio | 8.00
Capital With Capital Conservation Buffer Amount | $ 593,688
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio | 10.50
Capital Required To Be Well Capitalized Amount | $ 565,417
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio | 10.00
Common Equity Tier 1 Risk Based Capital Amount | $ 828,838
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 14.66
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 254,438
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 | $ 395,792
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio | 7.00
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount | $ 367,521
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 | $ 848,838
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 15.01
Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 339,250
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio | 6.00
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount | $ 480,604
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 | $ 452,334
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio | 8.00
Tier 1 Capital Amount | $ 848,838
Tier 1 Capital To Average Assets Ratio | 9.36
Tier 1 Capital Required For Capital Adequacy Amount | $ 362,698
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio | 4.00
Tier 1 Capital Required To Be Well Capitalized Amount | $ 453,372
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio | 5.00
Pegasus Bank [Member] |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |
Total Capital Amount | $ 74,397
Total Capital To Risk Weighted Assets Actual Ratio | 12.90
Capital Required For Capital Adequacy Amount | $ 46,124
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio | 8.00
Capital With Capital Conservation Buffer Amount | $ 60,538
Capital With Capital Conservation To Risk Based Weighted Assets Buffer Ratio | 10.50
Capital Required To Be Well Capitalized Amount | $ 57,656
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio | 10.00
Common Equity Tier 1 Risk Based Capital Amount | $ 69,519
Common Equity Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 12.06
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 25,945
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 | $ 40,359
Common Equity Tier 1 Risk Based Capital With Capital Conservation Buffer To Risk Weighted Assets Ratio | 7.00
Common Equity Tier 1 Risk Based Capital Required To Be Well Capitalized Amount | $ 37,476
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 | $ 69,519
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio | 12.06
Tier 1 Risk Based Capital Required For Capital Adequacy Amount | $ 34,593
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio | 6.00
Tier 1 Risk Based Capital With Capital Conservation Buffer Amount | $ 49,007
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 | $ 46,124
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio | 8.00
Tier 1 Capital Amount | $ 69,519
Tier 1 Capital To Average Assets Ratio | 7.52
Tier 1 Capital Required For Capital Adequacy Amount | $ 36,996
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio | 4.00
Tier 1 Capital Required To Be Well Capitalized Amount | $ 46,245
Tier 1 Capital Required To Be Well Capitalized To Average Assets Ratio | 5.00

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