XML 77 R60.htm IDEA: XBRL DOCUMENT
v3.20.4

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) $ in Thousands |  | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jan. 01, 2020 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2020 portfolio | Dec. 31, 2020 segment | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Loans held for sale, at fair value |  | $ 63,250 |  |  |  | $ 46,898 |  |  |
Percentage of income tax examination likelihood of tax benefits |  | 50.00% |  |  |  |  |  |  |
Number of distinct loan portfolios | portfolio |  |  |  | 7 |  |  |  |  |
Current expected credit losses, initial loss forecast term |  | 1 year |  |  |  |  |  |  |
Current expected credit losses, reversion period, term |  | 2 years |  |  |  |  |  |  |
Allowance for loan losses |  | $ 131,388 | [1] |  |  | 54,619 | [1] | $ 55,461 | $ 50,381
Shareholders' equity |  | (2,972,656) |  |  |  | (2,852,453) |  | (2,689,570) | (2,154,397)
Noncredit discount amount accreted into interest income | $ 11,800 |  |  |  |  |  |  |  |
Number of loan portfolios | portfolio |  |  |  | 4 |  |  |  |  |
Number of loan segments |  |  |  | 7 | 7 |  |  |  |
Retained Earnings |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Shareholders' equity |  | (783,892) |  |  |  | (682,185) |  | (527,684) | (413,130)
Adjustment |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Allowance for loan losses | 41,347 |  |  |  |  | 41,347 |  |  |
Allowance for credit losses on unfunded loan commitments | 4,549 |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 31,150 |  | (6,322) | 4,179
Adjustment | Retained Earnings |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 31,150 |  | $ (6,322) | $ 4,127
Adjustment | Retained Earnings | Accounting Standards Update 2016-13 |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Shareholders' equity |  |  |  |  |  | 31,200 |  |  |
Residential Mortgage Loans |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Loans held for sale, at fair value |  | $ 63,300 |  |  |  | $ 46,900 |  |  |
Acquired Loan Portfolio | Adjustment |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Allowance for loan losses | $ 27,100 |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  | 1 day |  |  |  |  |  |  |
Minimum | Core Deposits and Other Intangible Assets |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  | 5 years |  |  |  |  |  |  |
Minimum | Building and Building Improvements |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Useful lives for premises and equipment, years |  | 15 years |  |  |  |  |  |  |
Minimum | Furniture and Equipment |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Useful lives for premises and equipment, years |  | 3 years |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Maturity of short-term securities sold under agreements to repurchase |  | 4 days |  |  |  |  |  |  |
Maximum | Core Deposits and Other Intangible Assets |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Estimated useful lives of core deposits and customer relationships |  | 15 years |  |  |  |  |  |  |
Maximum | Building and Building Improvements |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Useful lives for premises and equipment, years |  | 39 years |  |  |  |  |  |  |
Maximum | Furniture and Equipment |  |  |  |  |  |  |  |  |
Basis Of Presentation And Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Useful lives for premises and equipment, years |  | 7 years |  |  |  |  |  |  |
[1] | Beginning January 1, 2020, calculation is based on current expected loss methodology. Prior to January 1, 2020, calculation was based on incurred loss methodology.

X
- Definition Basis of presentation and significant accounting policies. + References No definition available. + Details
Name: | onb_BasisOfPresentationAndSignificantAccountingPoliciesLineItems
Namespace Prefix: | onb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Current Expected Credit Losses, Initial Loss Forecast Term + References No definition available. + Details
Name: | onb_CurrentExpectedCreditLossesInitialLossForecastTerm
Namespace Prefix: | onb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Current Expected Credit Losses, Reversion Period, Term + References No definition available. + Details
Name: | onb_CurrentExpectedCreditLossesReversionPeriodTerm
Namespace Prefix: | onb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Financing Receivable, Number Of Distinct Loan Portfolios + References No definition available. + Details
Name: | onb_FinancingReceivableNumberOfDistinctLoanPortfolios
Namespace Prefix: | onb_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Financing Receivable, Number Of Loan Portfolios + References No definition available. + Details
Name: | onb_FinancingReceivableNumberOfLoanPortfolios
Namespace Prefix: | onb_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Financing Receivable, Number Of Loan Segments + References No definition available. + Details
Name: | onb_FinancingReceivableNumberOfLoanSegments
Namespace Prefix: | onb_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of days from transaction date that securities sold under agreement to repurchase mature. + References No definition available. + Details
Name: | onb_MaturityOfSecuritiesSoldUnderAgreementToRepurchase
Namespace Prefix: | onb_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Minimum percentage of likelihood of tax benefits being realized on examination required to recognize largest amount of tax benefit. + References No definition available. + Details
Name: | onb_PercentageOfIncomeTaxExaminationMinimumLikelihoodOfTaxBenefitsBeingRealizedUponExamination
Namespace Prefix: | onb_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(7)(2)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
Name: | us-gaap_FinancingReceivableAllowanceForCreditLosses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of interest income on financing receivable, from change in present value of expected cash flows, attributable to passage of time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82919204-210446 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919246-210447 + Details
Name: | us-gaap_FinancingReceivableChangeInPresentValueInterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_FiniteLivedIntangibleAssetUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 948 -SubTopic 310 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=120238483&loc=d3e48678-111004 + Details
Name: | us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121611286&loc=d3e11927-110247 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82919202-210446 + Details
Name: | us-gaap_OffBalanceSheetCreditLossLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
Name: | us-gaap_PropertyPlantAndEquipmentUsefulLife
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(g)(1)(ii)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 4.E) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(31)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(30)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 28 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612 Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571 + Details
Name: | us-gaap_StockholdersEquity
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=us-gaap_RetainedEarningsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CumulativeEffectPeriodOfAdoptionAxis=srt_CumulativeEffectPeriodOfAdoptionAdjustmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AdjustmentsForNewAccountingPronouncementsAxis=us-gaap_AccountingStandardsUpdate201613Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=onb_AcquiredLoanPortoflioMember
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: | us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=onb_CoreDepositsAndOtherIntangibleAssetsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_BuildingAndBuildingImprovementsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_FurnitureAndFixturesMember
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: |