XML 81 R64.htm IDEA: XBRL DOCUMENT
v3.25.0.1

Loans - Narrative (Details) - USD ($) |  |  | 12 Months Ended
--- | --- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
PCD loans | $ 12,300,000 | $ 34,800,000 |  |  |
Accrued interest | 32,600,000 | 35,100,000 | $ 32,600,000 | $ 35,100,000 |
Nonaccrual mortgage loans held for sale recorded at fair value | 0 | 0 | 0 | 0 |
Funding commitments | $ 35,000,000 | $ 1,600,000 | 35,000,000 | 1,600,000 |
Nonperforming Financial Instruments |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |
Interest income |  |  | $ 0 | $ 0 | $ 0

X
- Definition Loans And Leases Receivable, Impaired, Interest On Nonaccrual Loans + References No definition available. + Details
Name: | obnk_LoansAndLeasesReceivableImpairedInterestOnNonaccrualLoans
Namespace Prefix: | obnk_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

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 Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 20 -Name Accounting Standards Codification -Section 40 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481628/310-20-40-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481990/310-10-45-2 + Details
Name: | us-gaap_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, before allowance for credit loss, of accrued interest on financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B + Details
Name: | us-gaap_FinancingReceivableAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount at purchase price of financing receivable purchased with credit deterioration. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 19 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-19 + Details
Name: | us-gaap_FinancingReceivablePurchasedWithCreditDeteriorationAmountAtPurchasePrice
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 310 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481746/310-40-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 36 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-36 + Details
Name: | us-gaap_LoansAndLeasesReceivableImpairedCommitmentToLend
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value portion of mortgage loans held-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_MortgagesHeldForSaleFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentPerformanceStatusAxis=us-gaap_NonperformingFinancingReceivableMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |