XML 79 R60.htm IDEA: XBRL DOCUMENT
v3.22.0.1

Securities - Contractual Maturities (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Amortized Cost |  |
Due in one year or less | $ 0 |
Due after one year through five years | 0 |
Due after five years through ten years | 22,934 |
Due after ten years | 0 |
Held to maturity, amortized cost | 22,934 |
Fair Value |  |
Due in one year or less | 0 |
Due after one year through five years | 0 |
Due after five years through ten years | 25,117 |
Due after ten years | 0 |
Held to maturity, fair value | 25,117 | $ 41,205
Amortized Cost |  |
Due in one year or less | 5,618 |
Due after one year through five years | 117,609 |
Due after five years through ten years | 153,260 |
Due after ten years | 296,949 |
Available for sale, amortized cost | 1,497,458 | 971,595
Fair Value |  |
Due in one year or less | 5,623 |
Due after one year through five years | 120,398 |
Due after five years through ten years | 155,903 |
Due after ten years | 304,286 |
Available for sale, fair value | 1,504,728 | 1,004,674
Commercial mortgage-backed securities |  |
Amortized Cost |  |
Without single maturity date | 0 |
Fair Value |  |
Without single maturity date | 0 |
Amortized Cost |  |
Without single maturity date | 65,691 |
Available for sale, amortized cost | 65,691 | 10,814
Fair Value |  |
Without single maturity date | 64,243 |
Available for sale, fair value | 64,243 | 11,080
Residential mortgage-backed securities |  |
Amortized Cost |  |
Without single maturity date | 0 |
Fair Value |  |
Without single maturity date | 0 |
Amortized Cost |  |
Without single maturity date | 559,655 |
Available for sale, amortized cost | 559,655 | 207,742
Fair Value |  |
Without single maturity date | 557,801 |
Available for sale, fair value | 557,801 | 214,951
Commercial collateralized mortgage obligations |  |
Amortized Cost |  |
Without single maturity date | 0 |
Fair Value |  |
Without single maturity date | 0 |
Amortized Cost |  |
Without single maturity date | 20,000 |
Available for sale, amortized cost | 20,000 |
Fair Value |  |
Without single maturity date | 19,672 |
Available for sale, fair value | 19,672 |
Residential collateralized mortgage obligations |  |
Amortized Cost |  |
Without single maturity date | 0 |
Fair Value |  |
Without single maturity date | 0 |
Amortized Cost |  |
Without single maturity date | 196,691 |
Available for sale, amortized cost | 196,691 | 193,865
Fair Value |  |
Without single maturity date | 193,740 |
Available for sale, fair value | 193,740 | 195,343
Asset-backed securities |  |
Amortized Cost |  |
Without single maturity date | 0 |
Fair Value |  |
Without single maturity date | 0 |
Amortized Cost |  |
Without single maturity date | 81,985 |
Available for sale, amortized cost | 81,985 | 73,451
Fair Value |  |
Without single maturity date | 83,062 |
Available for sale, fair value | $ 83,062 | $ 74,328

X
- References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesFairValueAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

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), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue
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), with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingAfterYearTenFairValue
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), with single maturity date and allocated without single maturity date, maturing in rolling sixth through tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security, measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in rolling sixth through tenth fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue
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), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year through fifth year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCostBasis
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security, measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year through fifth year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue
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), without single maturity date and not allocated over maturity grouping. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27198-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), without single maturity date and not allocated over maturity grouping. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27198-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=123599081&loc=SL120269850-112803 + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestAfterAllowanceForCreditLossAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, 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 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 + Details
Name: | us-gaap_DebtSecuritiesAvailableForSaleAmortizedCostExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount excluding accrued interest, 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/2009/role/commonPracticeRef -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_DebtSecuritiesAvailableForSaleExcludingAccruedInterest
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesFairValueAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing after tenth rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesRollingAfterTenYearsFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in second through fifth rolling fiscal year following latest fiscal year. For interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date. + References No definition available. + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity), without single maturity date and not allocated over maturity grouping. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5B -URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269825-111563 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3A -URI http://asc.fasb.org/extlink&oid=123599081&loc=SL120269850-112803 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) without single maturity date and not allocated over maturity grouping. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123599081&loc=d3e62586-112803 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesDebtMaturitiesWithoutSingleMaturityDateNetCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27232-111563 Reference 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123581744&loc=SL120269820-111563 + Details
Name: | us-gaap_HeldToMaturitySecuritiesFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesDebtMaturitiesAmortizedCostRollingMaturityAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in next rolling fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach. + References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesDebtMaturitiesNextRollingTwelveMonthsAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing after rolling tenth fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach. + References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesDebtMaturitiesRollingAfterTenYearsAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in sixth through tenth rolling fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach. + References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesDebtMaturitiesRollingYearSixThroughTenAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity) with single maturity date and allocated without single maturity date, maturing in second through fifth rolling fiscal year following current statement of financial position date. For interim and annual periods when interim period is reported on rolling approach. + References No definition available. + Details
Name: | us-gaap_HeldtomaturitySecuritiesDebtMaturitiesRollingYearTwoThroughFiveAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

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

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

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