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Namespace Prefix:	sbfg_
Data Type:	xbrli:stringItemType
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Period Type:	duration

The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

No definition available.

Name:	sbfg_EarningsPerSharesDiluted
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Data Type:	dtr:perShareItemType
Balance Type:	na
Period Type:	duration

Face amount or stated value per share of common stock.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_CommonStockParOrStatedValuePerShare
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Data Type:	dtr-types:perShareItemType
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Period Type:	instant

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

Name:	us-gaap_CommonStockSharesAuthorized
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21463-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Name:	us-gaap_CommonStockSharesOutstanding
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Data Type:	xbrli:sharesItemType
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Period Type:	instant

Price of a single share of a number of saleable stocks of a company.

No definition available.