XML 78 R63.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Investment Securities - Amortized Cost and Fair Value of Available-for-Sale and Held-to-Maturity Investment Securities Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | $ 7,384,033 | $ 5,784,754
Unrealized Gains | 112,282 | 197,714
Unrealized Losses | (118,235) | (11,385)
Basis Adjustments | 3,986 | (968)
Fair Value | 7,382,066 | 5,970,115
U.S. Treasury |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 234,555 | 9,909
Unrealized Gains | 1,233 | 299
Unrealized Losses | (7,751) | 0
Basis Adjustments | 7,547 | 0
Fair Value | 235,584 | 10,208
U.S. government-sponsored entities and agencies |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 1,575,994 | 841,133
Unrealized Gains | 7,354 | 5,744
Unrealized Losses | (37,014) | (3,921)
Basis Adjustments | (3,561) | (968)
Fair Value | 1,542,773 | 841,988
Mortgage-backed securities |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 3,737,484 | 3,249,002
Unrealized Gains | 27,421 | 91,086
Unrealized Losses | (66,074) | (990)
Basis Adjustments | 0 | 0
Fair Value | 3,698,831 | 3,339,098
States and political subdivisions |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 1,587,172 | 1,405,868
Unrealized Gains | 69,696 | 86,325
Unrealized Losses | (1,882) | (31)
Basis Adjustments | 0 | 0
Fair Value | 1,654,986 | 1,492,162
Pooled trust preferred securities |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 13,756 | 13,763
Unrealized Gains | 0 | 0
Unrealized Losses | (4,260) | (5,850)
Basis Adjustments | 0 | 0
Fair Value | 9,496 | 7,913
Other securities |  |
Schedule Of Available For Sale And Held To Maturity Securities [Line Items] |  |
Amortized Cost | 235,072 | 265,079
Unrealized Gains | 6,578 | 14,260
Unrealized Losses | (1,254) | (593)
Basis Adjustments | 0 | 0
Fair Value | $ 240,396 | $ 278,746

X
- Definition Debt Securities, Available-For-Sale, Accumulated Basis Adjustments, Before Tax + References No definition available. + Details
Name: | onb_DebtSecuritiesAvailableForSaleAccumulatedBasisAdjustmentsBeforeTax
Namespace Prefix: | onb_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Schedule of available for sale and held to maturity securities. + References No definition available. + Details
Name: | onb_ScheduleOfAvailableForSaleAndHeldToMaturitySecuritiesLineItems
Namespace Prefix: | onb_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
Name: | us-gaap_AvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

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

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

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

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