XML 28 R58.htm IDEA: XBRL DOCUMENT
v3.20.1

Fair Value Measurements Fair Value Measurement, Measured On Non-Recurring Basis, Signfiicant Unobservable Inputs, Quantitative Information (Details) - Fair Value, Nonrecurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands | Mar. 31, 2020 | Mar. 31, 2019
--- | --- | ---
Nonaccruing Loans [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value Disclosure | $ 22,746 | $ 9,712
Real estate and other repossessed assets [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value Disclosure | 400 | 144
Discounted Cash Flow [Member] | Nonaccruing Loans [Member] | Management knowledge of Industry [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value Disclosure | 22,746 | 9,712
Appraised Value, as Adjusted [Member] | Real estate and other repossessed assets [Member] | Marketability adjustments off appraised value |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Assets, Fair Value Disclosure | $ 400 | $ 144
Minimum [Member] | Nonaccruing Loans [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 6.00% | 14.00%
Minimum [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value Measurement, Percentage of Appraised Value. Minimum | 87.00% | 75.00%
Maximum [Member] | Nonaccruing Loans [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 71.00% | 74.00%
Maximum [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value Measurement, Percentage of Appraised Value. Minimum | 87.00% | 85.00%
Weighted Average [Member] | Nonaccruing Loans [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance | 36.00% | 31.00%
Weighted Average [Member] | Real estate and other repossessed assets [Member] |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Fair Value Measurement, Percentage of Appraised Value. Minimum | 87.00% | 79.00%

X
- Definition Fair Value Measurement, Percentage of appraised value + References No definition available. + Details
Name: | bokf_FairValueMeasurementPercentageofappraisedvalue
Namespace Prefix: | bokf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair Value of Impaired Loans as Percentage of Unpaid Principal Balance + References No definition available. + Details
Name: | bokf_FairValueofImpairedLoansasPercentageofUnpaidPrincipalBalance
Namespace Prefix: | bokf_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_AssetsFairValueDisclosure
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_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisValuationTechniquesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsNonrecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=bokf_FairValueNonaccruingLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=bokf_FairValueRealEstateAndOtherRepossessedAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_ValuationTechniqueDiscountedCashFlowMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=bokf_ManagementknowledgeofIndustryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=bokf_ValuationTechniqueAppraisedValueasAdjustedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=bokf_MarketabilityadjustmentsoffappraisedvalueDomain
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |