XML 63 R50.htm IDEA: XBRL DOCUMENT
v3.20.2

Loans and Allowance for Credit Losses on Loans - TDR (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 USD ($) contract | Mar. 31, 2020 USD ($) | Sep. 30, 2019 USD ($) contract | Mar. 31, 2019 USD ($) | Sep. 30, 2020 USD ($) contract | Sep. 30, 2019 USD ($) contract | Dec. 31, 2019 USD ($)
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract | 1 |  | 1 |  | 3 | 7 |
Pre-modification recorded investment | $ 154,000 |  | $ 1,159,000 |  | $ 410,000 | $ 1,694,000 |
Post-modification recorded investment | 153,000 |  | $ 1,122,000 |  | 404,000 | $ 1,546,000 |
TDR's defaulted |  |  |  |  |  |  |
Pre-modification outstanding recorded investment during the period |  | $ 0 |  | $ 0 |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | 18,694,000 |  |  |  | 18,694,000 |  |
Home Affordable Modification Program [Member] |  |  |  |  |  |  |
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract |  |  |  |  |  | 1 |
Pre-modification recorded investment |  |  |  |  |  | $ 39,000 |
Post-modification recorded investment |  |  |  |  |  | $ 34,000 |
Residential Owner Occupied Loan [Member] | Home Affordable Modification Program [Member] |  |  |  |  |  |  |
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract |  |  |  |  |  | 3 |
Pre-modification recorded investment |  |  |  |  |  | $ 399,000 |
Post-modification recorded investment |  |  |  |  |  | $ 297,000 |
Commercial Real Estate, Owner Occupied General Purpose Loan [Member] |  |  |  |  |  |  |
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract |  |  | 1 |  |  | 2 |
Pre-modification recorded investment |  |  | $ 1,159,000 |  |  | $ 1,217,000 |
Post-modification recorded investment |  |  | $ 1,122,000 |  |  | $ 1,177,000 |
Real estate - commercial | Commercial Real Estate, Owner Occupied General Purpose Loan [Member] |  |  |  |  |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | $ 9,583,000 |  |  |  | $ 9,583,000 |  |
Real estate - residential | Residential Owner Occupied Loan [Member] | Home Affordable Modification Program [Member] |  |  |  |  |  |  |
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract | 1 |  |  |  | 3 |  |
Pre-modification recorded investment | $ 154,000 |  |  |  | $ 410,000 |  |
Post-modification recorded investment | 153,000 |  |  |  | 404,000 |  |
Real estate - residential | HELOC | Residential Owner Occupied Loan [Member] | Others [Member] |  |  |  |  |  |  |
Troubled debt restructurings - modified during the period |  |  |  |  |  |  |
# of contracts | contract |  |  |  |  |  | 1 |
Pre-modification recorded investment |  |  |  |  |  | $ 39,000 |
Post-modification recorded investment |  |  |  |  |  | $ 38,000 |
Commercial |  |  |  |  |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | 1,424,000 |  |  |  | 1,424,000 |  | $ 4,299,000
90 Days or Greater Past Due |  |  |  |  |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | 12,577,000 |  |  |  | 12,577,000 |  |
90 Days or Greater Past Due | Real estate - commercial | Commercial Real Estate, Owner Occupied General Purpose Loan [Member] |  |  |  |  |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | 7,618,000 |  |  |  | 7,618,000 |  |
90 Days or Greater Past Due | Commercial |  |  |  |  |  |  |
Other information |  |  |  |  |  |  |
Total Past Due | $ 1,368,000 |  |  |  | $ 1,368,000 |  | $ 2,103,000

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

X
- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953682-111524 + Details
Name: | us-gaap_FinancingReceivableModificationsSubsequentDefaultRecordedInvestment1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of financing receivable past due. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 80 -URI http://asc.fasb.org/extlink&oid=121647567&loc=SL82922355-210448 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=121599337&loc=SL82919253-210447 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953401-111524 + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentPastDue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_InternalCreditAssessmentAxis=osbc_HomeAffordableModificationProgramMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=osbc_ResidentialOwnerOccupiedLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=osbc_CommercialRealEstateOwnerOccupiedGeneralPurposeLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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