XML 59 R48.htm IDEA: XBRL DOCUMENT
v3.23.3

Loans and Allowance for Credit Losses on Loans - Loan Modifications (Details) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2023 USD ($)
Financing Receivable |
Total Loans modified | $ 43,003
Total Loan Segment Modified to Total Loan Segment | 1.10%
Weighted-Average Term Extension (In Months) | 11 months 5 days
Weighted-Average Interest Rate Change | 5.00%
Weighted-Average Delay of Payment (In Months) | 7 months 5 days
90 Days or Greater Past Due |
Financing Receivable |
Total Loans modified | $ 979
Total Past Due |
Financing Receivable |
Total Loans modified | 979
Current |
Financing Receivable |
Total Loans modified | 42,024
Term Extension |
Financing Receivable |
Total Loans modified | 31,416
Combination - Term Extension and Payment Delay |
Financing Receivable |
Total Loans modified | 10,608
Combination - Term Extension and Interest Rate Reduction |
Financing Receivable |
Total Loans modified | 979
Commercial |
Financing Receivable |
Total Loans modified | $ 2,692
Total Loan Segment Modified to Total Loan Segment | 0.30%
Weighted-Average Term Extension (In Months) | 6 months 22 days
Weighted-Average Interest Rate Change | 5.00%
Commercial | 90 Days or Greater Past Due |
Financing Receivable |
Total Loans modified | $ 979
Commercial | Total Past Due |
Financing Receivable |
Total Loans modified | 979
Commercial | Current |
Financing Receivable |
Total Loans modified | 1,713
Commercial | Term Extension |
Financing Receivable |
Total Loans modified | 1,713
Commercial | Combination - Term Extension and Interest Rate Reduction |
Financing Receivable |
Total Loans modified | 979
Commercial real estate - Investor |
Financing Receivable |
Total Loans modified | $ 23,363
Total Loan Segment Modified to Total Loan Segment | 2.20%
Weighted-Average Term Extension (In Months) | 9 months 24 days
Weighted-Average Delay of Payment (In Months) | 7 months 5 days
Commercial real estate - Investor | Current |
Financing Receivable |
Total Loans modified | $ 23,363
Commercial real estate - Investor | Term Extension |
Financing Receivable |
Total Loans modified | 12,755
Commercial real estate - Investor | Combination - Term Extension and Payment Delay |
Financing Receivable |
Total Loans modified | 10,608
Commercial real estate - Owner occupied |
Financing Receivable |
Total Loans modified | $ 16,218
Total Loan Segment Modified to Total Loan Segment | 2.00%
Weighted-Average Term Extension (In Months) | 14 months
Commercial real estate - Owner occupied | Current |
Financing Receivable |
Total Loans modified | $ 16,218
Commercial real estate - Owner occupied | Term Extension |
Financing Receivable |
Total Loans modified | 16,218
Residential real estate - Owner occupied |
Financing Receivable |
Total Loans modified | $ 437
Total Loan Segment Modified to Total Loan Segment | 0.20%
Weighted-Average Term Extension (In Months) | 2 months
Residential real estate - Owner occupied | Current |
Financing Receivable |
Total Loans modified | $ 437
Residential real estate - Owner occupied | Term Extension |
Financing Receivable |
Total Loans modified | 437
Multifamily |
Financing Receivable |
Total Loans modified | $ 254
Total Loan Segment Modified to Total Loan Segment | 0.10%
Weighted-Average Term Extension (In Months) | 16 months
Multifamily | Current |
Financing Receivable |
Total Loans modified | $ 254
Multifamily | Term Extension |
Financing Receivable |
Total Loans modified | 254
HELOC |
Financing Receivable |
Total Loans modified | $ 39
Total Loan Segment Modified to Total Loan Segment | 0.00%
Weighted-Average Term Extension (In Months) | 24 months
HELOC | Current |
Financing Receivable |
Total Loans modified | $ 39
HELOC | Term Extension |
Financing Receivable |
Total Loans modified | $ 39

X
- Definition Percentage of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables. + References No definition available. + Details
Name: | osbc_FinancingReceivableModifiedInPeriodToTotalFinancingReceivablesPercentage
Namespace Prefix: | osbc_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of delay in payment financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | osbc_FinancingReceivableModifiedWeightedAveragePaymentDelayFromModification
Namespace Prefix: | osbc_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Accumulated amortized cost excluding accrued interest, of financing receivable modified for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-42 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestModifiedAccumulated
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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-42 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 42 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-42 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 33 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-33 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 34 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-34 + Details
Name: | us-gaap_FinancingReceivableModificationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A + Details
Name: | us-gaap_FinancingReceivableModifiedWeightedAverageInterestRateDecreaseFromModification
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 12A -Publisher FASB -URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A + Details
Name: | us-gaap_FinancingReceivableModifiedWeightedAverageTermIncreaseFromModification
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=osbc_ExtendedMaturityAndPaymentDelayMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityAndInterestRateReductionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=osbc_CommercialRealEstateInvestorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=osbc_CommercialRealEstateOwnerOccupiedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=osbc_RealEstateOwnerOccupiedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=osbc_MultiFamilyLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_HomeEquityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |