XML 78 R65.htm IDEA: XBRL DOCUMENT
v3.20.4

Loans and Allowances for Credit Losses, Nonaccrual (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | $ 234,693 | $ 180,951
Financing Receivable, Nonaccrual, No Allowance | 167,878 |
Financing receivable, Nonaccrual, With Allowance | 66,815 |
Financing Receivable, Nonaccrual, Related Allowance | 22,441 |
Commercial [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 167,159 | 115,416
Financing Receivable, Nonaccrual, No Allowance | 113,945 |
Financing receivable, Nonaccrual, With Allowance | 53,214 |
Financing Receivable, Nonaccrual, Related Allowance | 19,052 |
Commercial [Member] | Energy [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 125,059 | 91,722
Financing Receivable, Nonaccrual, No Allowance | 76,633 |
Financing receivable, Nonaccrual, With Allowance | 48,426 |
Financing Receivable, Nonaccrual, Related Allowance | 16,478 |
Commercial [Member] | Healthcare [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 3,645 | 4,480
Financing Receivable, Nonaccrual, No Allowance | 3,645 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 |
Commercial [Member] | Services [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 25,598 | 7,483
Financing Receivable, Nonaccrual, No Allowance | 20,810 |
Financing receivable, Nonaccrual, With Allowance | 4,788 |
Financing Receivable, Nonaccrual, Related Allowance | 2,574 |
Commercial [Member] | General business [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 12,857 |
Financing Receivable, Nonaccrual, No Allowance | 12,857 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 |
Commercial real estate [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 27,246 | 27,626
Financing Receivable, Nonaccrual, No Allowance | 13,645 |
Financing receivable, Nonaccrual, With Allowance | 13,601 |
Financing Receivable, Nonaccrual, Related Allowance | 3,389 |
Loans to individuals [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 40,288 |
Financing Receivable, Nonaccrual, No Allowance | 40,288 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 |
Loans to individuals [Member] | Residential mortgage [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 32,228 |
Financing Receivable, Nonaccrual, No Allowance | 32,228 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 |
Loans to individuals [Member] | Personal [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 319 | $ 287
Financing Receivable, Nonaccrual, No Allowance | 319 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | 0 |
US Government Agency Insured Loans | Loans to individuals [Member] | Residential mortgage [Member] |  |
Financing Receivable, Nonaccrual [Line Items] |  |
Nonaccrual | 7,741 |
Financing Receivable, Nonaccrual, No Allowance | 7,741 |
Financing receivable, Nonaccrual, With Allowance | 0 |
Financing Receivable, Nonaccrual, Related Allowance | $ 0 |

X
- Definition Financing Receivable, Nonaccrual, Related Allowance + References No definition available. + Details
Name: | bokf_FinancingReceivableNonaccrualRelatedAllowance
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing receivable, nonaccrual, with allowance + References No definition available. + Details
Name: | bokf_FinancingReceivableNonaccrualWithAllowance
Namespace Prefix: | bokf_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of financing receivable on nonaccrual status with no allowance for credit loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableNonaccrualNoAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_FinancingReceivableNonaccrualStatusLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of financing receivable on nonaccrual status. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5111-111524 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bokf_EnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_HealthCareMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bokf_ServicesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=bokf_GeneralBusinessClassMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=bokf_LoanstoindividualsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoansInsuredOrGuaranteedByGovernmentAuthoritiesAxis=us-gaap_UsGovernmentAgencyInsuredLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |