XML 20 R121.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Segment Information - Results of Operations and Selected Financial Information (Detail) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2013 | Sep. 30, 2013 | Jun. 30, 2013 | Mar. 31, 2013 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) | $ 47,319 us-gaap_InterestIncomeExpenseNet | $ 46,514 us-gaap_InterestIncomeExpenseNet | $ 45,489 us-gaap_InterestIncomeExpenseNet | $ 42,029 us-gaap_InterestIncomeExpenseNet | $ 41,921 us-gaap_InterestIncomeExpenseNet | $ 40,712 us-gaap_InterestIncomeExpenseNet | $ 40,630 us-gaap_InterestIncomeExpenseNet | $ 40,256 us-gaap_InterestIncomeExpenseNet | $ 181,351 us-gaap_InterestIncomeExpenseNet | $ 163,519 us-gaap_InterestIncomeExpenseNet | $ 164,815 us-gaap_InterestIncomeExpenseNet
Provision for loan losses | 1,840 us-gaap_ProvisionForLoanAndLeaseLosses | (3,115)us-gaap_ProvisionForLoanAndLeaseLosses | 3,129 us-gaap_ProvisionForLoanAndLeaseLosses | 1,218 us-gaap_ProvisionForLoanAndLeaseLosses | 454 us-gaap_ProvisionForLoanAndLeaseLosses | (12)us-gaap_ProvisionForLoanAndLeaseLosses | 516 us-gaap_ProvisionForLoanAndLeaseLosses | 300 us-gaap_ProvisionForLoanAndLeaseLosses | 3,072 us-gaap_ProvisionForLoanAndLeaseLosses | 1,258 us-gaap_ProvisionForLoanAndLeaseLosses | 3,100 us-gaap_ProvisionForLoanAndLeaseLosses
Noninterest income | 24,302 us-gaap_NoninterestIncome | 24,938 us-gaap_NoninterestIncome | 23,611 us-gaap_NoninterestIncome | 23,562 us-gaap_NoninterestIncome | 22,235 us-gaap_NoninterestIncome | 23,652 us-gaap_NoninterestIncome | 21,733 us-gaap_NoninterestIncome | 22,535 us-gaap_NoninterestIncome | 96,413 us-gaap_NoninterestIncome | 90,155 us-gaap_NoninterestIncome | 87,717 us-gaap_NoninterestIncome
Depreciation and amortization |  |  |  |  |  |  |  |  | 11,349 us-gaap_DepreciationDepletionAndAmortization | 11,077 us-gaap_DepreciationDepletionAndAmortization | 10,840 us-gaap_DepreciationDepletionAndAmortization
Other expenses |  |  |  |  |  |  |  |  | 172,172 banf_NoninterestExpenseExcludingDepreciationAndAmortization | 160,497 banf_NoninterestExpenseExcludingDepreciationAndAmortization | 159,588 banf_NoninterestExpenseExcludingDepreciationAndAmortization
Income before taxes |  |  |  |  |  |  |  |  | 91,171 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments | 80,842 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments | 79,004 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments
Total assets | 6,574,972 us-gaap_Assets |  |  |  | 6,038,974 us-gaap_Assets |  |  |  | 6,574,972 us-gaap_Assets | 6,038,974 us-gaap_Assets | 6,022,250 us-gaap_Assets
Capital expenditures |  |  |  |  |  |  |  |  | 11,490 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | 13,896 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment | 13,438 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment
Operating Segments [Member] | Metropolitan Banks [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  | 59,923 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 56,346 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 54,062 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Provision for loan losses |  |  |  |  |  |  |  |  | 3,077 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | (154)us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 1,202 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Noninterest income |  |  |  |  |  |  |  |  | 13,752 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 12,881 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 11,222 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Depreciation and amortization |  |  |  |  |  |  |  |  | 2,216 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 2,178 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 1,956 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Other expenses |  |  |  |  |  |  |  |  | 32,300 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 31,396 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 29,511 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Income before taxes |  |  |  |  |  |  |  |  | 36,082 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 35,807 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 32,615 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Total assets | 2,298,828 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember |  |  |  | 2,079,444 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember |  |  |  | 2,298,828 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 2,079,444 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 1,996,539 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Capital expenditures |  |  |  |  |  |  |  |  | 1,948 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 5,534 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember | 4,099 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_MetropolitanBanksMember
Operating Segments [Member] | Community Banks [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  | 116,935 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 102,705 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 105,966 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Provision for loan losses |  |  |  |  |  |  |  |  | (488)us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 1,205 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 1,607 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Noninterest income |  |  |  |  |  |  |  |  | 51,415 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 48,418 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 43,809 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Depreciation and amortization |  |  |  |  |  |  |  |  | 7,277 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 7,011 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 6,898 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Other expenses |  |  |  |  |  |  |  |  | 89,888 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 84,011 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 80,535 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Income before taxes |  |  |  |  |  |  |  |  | 71,673 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 58,896 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 60,735 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Total assets | 4,113,783 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember |  |  |  | 3,764,429 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember |  |  |  | 4,113,783 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 3,764,429 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 3,801,653 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Capital expenditures |  |  |  |  |  |  |  |  | 7,972 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 6,445 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember | 8,045 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_CommunityBanksMember
Operating Segments [Member] | Other Financial Services [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  | 6,155 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 6,239 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 7,055 us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Provision for loan losses |  |  |  |  |  |  |  |  | 481 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 121 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 182 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Noninterest income |  |  |  |  |  |  |  |  | 28,079 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 25,659 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 29,624 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Depreciation and amortization |  |  |  |  |  |  |  |  | 522 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 521 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 485 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Other expenses |  |  |  |  |  |  |  |  | 22,304 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 21,604 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 22,056 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Income before taxes |  |  |  |  |  |  |  |  | 10,927 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 9,652 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 13,956 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Total assets | 145,814 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  |  |  | 103,656 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember |  |  |  | 145,814 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 103,656 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 186,473 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Capital expenditures |  |  |  |  |  |  |  |  | 121 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 219 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember | 398 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = us-gaap_AllOtherSegmentsMember
Operating Segments [Member] | Executive, Operations & Support [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net interest income (expense) |  |  |  |  |  |  |  |  | (1,662)us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | (1,771)us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | (2,268)us-gaap_InterestIncomeExpenseNet / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Provision for loan losses |  |  |  |  |  |  |  |  | 2 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 86 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 109 us-gaap_ProvisionForLoanAndLeaseLosses / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Noninterest income |  |  |  |  |  |  |  |  | 69,442 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 59,298 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 56,848 us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Depreciation and amortization |  |  |  |  |  |  |  |  | 1,334 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 1,367 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 1,501 us-gaap_DepreciationDepletionAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Other expenses |  |  |  |  |  |  |  |  | 27,998 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 23,818 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 27,783 banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Income before taxes |  |  |  |  |  |  |  |  | 38,446 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 32,256 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 25,187 us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Total assets | 679,194 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember |  |  |  | 703,294 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember |  |  |  | 679,194 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 703,294 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 602,342 us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Capital expenditures |  |  |  |  |  |  |  |  | 1,449 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 1,698 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember | 896 us-gaap_PaymentsToAcquirePropertyPlantAndEquipment / us-gaap_ConsolidationItemsAxis = us-gaap_OperatingSegmentsMember / us-gaap_StatementBusinessSegmentsAxis = banf_ExecutiveOperationsAndSupportMember
Eliminations [Member] |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |
Noninterest income |  |  |  |  |  |  |  |  | (66,275)us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (56,101)us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (53,786)us-gaap_NoninterestIncome / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember
Other expenses |  |  |  |  |  |  |  |  | (318)banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (332)banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (297)banf_NoninterestExpenseExcludingDepreciationAndAmortization / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember
Income before taxes |  |  |  |  |  |  |  |  | (65,957)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (55,769)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | (53,489)us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember
Total assets | $ (662,647)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember |  |  |  | $ (611,849)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember |  |  |  | $ (662,647)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | $ (611,849)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember | $ (564,757)us-gaap_Assets / us-gaap_ConsolidationItemsAxis = us-gaap_IntersegmentEliminationMember

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