Stockholder's Equity (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012
Required capital amounts and company respective ratios
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	6.00%
Tier 1 Capital Required To Be Well Capitalized To Average assets Ratio	5.00%
BancFirst Corporation [Member]
Required capital amounts and company respective ratios
Total Capital To Risk Weighted Assets Actual Amount	500,048
Total Capital To Risk Weighted Assets Actual Ratio	14.62%
Capital required For Capital Adequacy Amount	273,588
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	8.00%
Tier 1 Risk Based Capital Amount	462,612
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	13.53%
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	136,794
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	4.00%
Tier 1 Capital Amount	462,612
Tier 1 Capital To Average Assets Ratio	8.24%
Tier 1 Capital Required For Capital Adequacy Amount	170,193
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	3.00%
BancFirst [Member]
Required capital amounts and company respective ratios
Total Capital To Risk Weighted Assets Actual Amount	475,563
Total Capital To Risk Weighted Assets Actual Ratio	13.94%
Capital required For Capital Adequacy Amount	272,894
Capital Required For Capital Adequacy to Risk Weighted Assets Ratio	8.00%
Capital Required To Be Well Capitalized Amount	341,118
Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	10.00%
Tier 1 Risk Based Capital Amount	438,127
Tier 1 Risk Based Capital To Risk Weighted Assets Ratio	12.84%
Tier 1 Risk Based Capital Required For Capital Adequacy Amount	136,447
Tier 1 Risk Based Capital Required For Capital Adequacy To Risk Weighted Assets Ratio	4.00%
Tier 1 Risk Based Capital Required To Be well Capitalized Amount	204,671
Tier 1 Risk Based Capital Required To Be Well Capitalized To Risk Weighted Assets Ratio	6.00%
Tier 1 Capital Amount	438,127
Tier 1 Capital To Average Assets Ratio	7.81%
Tier 1 Capital Required For Capital Adequacy Amount	169,614
Tier 1 Capital Required For Capital Adequacy To Average Assets Ratio	3.00%
Tier 1 Capital Required To Be Well Capitalized Amount	282,690
Tier 1 Capital Required To Be Well Capitalized To Average assets Ratio	5.00%

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