XML 47 R45.htm IDEA: XBRL DOCUMENT v2.4.1.9

Loans and Allowance for Loan Losses - Loans Outstanding by Impairment Methodology (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	$ 90,978us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment	$ 56,575us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Collectively evaluated for impairment	3,752,610us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment	3,465,541us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Loans acquired with deteriorated credit quality	14,154us-gaap_FinancingReceivableAcquiredWithDeterioratedCreditQuality	20,154us-gaap_FinancingReceivableAcquiredWithDeterioratedCreditQuality
Non-residential Real Estate Owner Occupied [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	6,058us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOwnerOccupiedMember	6,555us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOwnerOccupiedMember
Collectively evaluated for impairment	480,800us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOwnerOccupiedMember	452,239us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOwnerOccupiedMember
Non-residential Real Estate Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	35,369us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOtherMember	25,934us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOtherMember
Collectively evaluated for impairment	921,813us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOtherMember	853,571us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonResidentialRealEstateOtherMember
Residential Real Estate Permanent Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	7,488us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstatePermanentMortgageMember	7,477us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstatePermanentMortgageMember
Collectively evaluated for impairment	305,289us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstatePermanentMortgageMember	265,727us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstatePermanentMortgageMember
Residential Real Estate All Other [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	13,291us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstateAllOtherMember	7,562us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstateAllOtherMember
Collectively evaluated for impairment	626,330us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstateAllOtherMember	560,185us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ResidentialRealEstateAllOtherMember
Non-consumer Non-real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	26,472us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonConsumerNonRealEstateMember	6,657us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonConsumerNonRealEstateMember
Collectively evaluated for impairment	937,138us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonConsumerNonRealEstateMember	821,382us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_NonConsumerNonRealEstateMember
Consumer Non-real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	2,161us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ConsumerNonRealEstateMember	2,082us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ConsumerNonRealEstateMember
Collectively evaluated for impairment	240,041us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ConsumerNonRealEstateMember	223,880us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_ConsumerNonRealEstateMember
Other Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Individually evaluated for impairment	139us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_OtherLoansMember	308us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_OtherLoansMember
Collectively evaluated for impairment	164,989us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_OtherLoansMember	147,903us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_OtherLoansMember
Acquired Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Collectively evaluated for impairment	76,210us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_AcquiredLoansMember	140,654us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment / us-gaap_FinancialInstrumentAxis = banf_AcquiredLoansMember
Loans acquired with deteriorated credit quality	$ 14,154us-gaap_FinancingReceivableAcquiredWithDeterioratedCreditQuality / us-gaap_FinancialInstrumentAxis = banf_AcquiredLoansMember	$ 20,154us-gaap_FinancingReceivableAcquiredWithDeterioratedCreditQuality / us-gaap_FinancialInstrumentAxis = banf_AcquiredLoansMember

X

- Details

Name:	us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The balance of financing receivables that were acquired with deteriorated credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableAcquiredWithDeterioratedCreditQuality
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableCollectivelyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (h)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableIndividuallyEvaluatedForImpairment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_AcquiredLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_ConsumerNonRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_NonConsumerNonRealEstateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_NonResidentialRealEstateOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_NonResidentialRealEstateOwnerOccupiedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_OtherLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_ResidentialRealEstateAllOtherMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=banf_ResidentialRealEstatePermanentMortgageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: