XML 74 R58.htm IDEA: XBRL DOCUMENT
v3.20.4

Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities [Line Items] |  |
Amortized Cost | $ 146,609 | $ 100,114
Gross Unrealized Gains | 2,854 | 1,039
Gross Unrealized Losses | (57) | (205)
Fair Value | 149,406 | 100,948
U.S. Treasury and Government agencies [Member] |  |
Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities [Line Items] |  |
Amortized Cost | 6,541 | 12,023
Gross Unrealized Gains | 323 | 181
Gross Unrealized Losses |  | (2)
Fair Value | 6,864 | 12,202
Mortgage-backed securities [Member] |  |
Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities [Line Items] |  |
Amortized Cost | 125,973 | 77,892
Gross Unrealized Gains | 1,845 | 492
Gross Unrealized Losses | (57) | (202)
Fair Value | 127,761 | 78,182
State and political subdivisions [Member] |  |
Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities [Line Items] |  |
Amortized Cost | 11,595 | 10,199
Gross Unrealized Gains | 680 | 366
Gross Unrealized Losses |  | (1)
Fair Value | 12,275 | $ 10,564
Other corporate securities [Member] |  |
Available-for-Sale Securities (Details) - Schedule of amortized cost and fair values with gross unrealized gains and losses of available-for-sale securities [Line Items] |  |
Amortized Cost | 2,500 |
Gross Unrealized Gains | 6 |
Gross Unrealized Losses |  |
Fair Value | $ 2,506 |

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

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesAmortizedCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossUnrealizedGains
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesGrossUnrealizedLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=sbfg_OtherCorporateSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |