XML 48 R45.htm IDEA: XBRL DOCUMENT v2.4.1.9

Loans - Repossessed Assets (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Real estate - residential
Repossessed and foreclosed assets
Real estate assets in process of foreclosure	$ 3,000,000osbc_MortgageLoansInProcessOfForeclosureAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember	$ 3,500,000osbc_MortgageLoansInProcessOfForeclosureAmount / us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis = us-gaap_ResidentialPortfolioSegmentMember
Other Assets
Repossessed and foreclosed assets
Repossessed assets	$ 0us-gaap_OtherForeclosedAssets / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember	$ 0us-gaap_OtherForeclosedAssets / us-gaap_BalanceSheetLocationAxis = us-gaap_OtherAssetsMember

X

- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

No definition available.

+ Details

Name:	osbc_MortgageLoansInProcessOfForeclosureAmount
Namespace Prefix:	osbc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Carrying amount as of the balance sheet date of assets other than real property that were received in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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- Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: