Name:	sybt_AdvancesFromFederalHomeLoanBanksPrincipalDueAtMaturity
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The weighted average interest rate applicable to the Federal Home Loan Bank advances maturing after the fourteenth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearFourteen
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Data Type:	num:percentItemType
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The weighted average interest rate applicable to the Federal Home Loan Bank advances maturing within one year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearOne
Namespace Prefix:	sybt_
Data Type:	num:percentItemType
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The weighted average interest rate applicable to the Federal Home Loan Bank advances maturing after the seventh fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearSeven
Namespace Prefix:	sybt_
Data Type:	num:percentItemType
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Period Type:	instant

The weighted average interest rate applicable to the Federal Home Loan Bank advances maturing after the sixth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearSix
Namespace Prefix:	sybt_
Data Type:	num:percentItemType
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The weighted average interest rate applicable to the Federal Home Loan Bank advances maturing after the tenth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearTen
Namespace Prefix:	sybt_
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Amount of Federal Home Loan Bank advances maturing in the sixth fiscal year following the latest fiscal year.

No definition available.

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Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Amount of Federal Home Loan Bank advances maturing in the seventh fiscal year following the latest fiscal year.

No definition available.

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Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Amount of Federal Home Loan Bank advances maturing in the tenth fiscal year following the latest fiscal year.

No definition available.

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Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Amount of Federal Home Loan Bank advances maturing in the fourteenth fiscal year following the latest fiscal year.

No definition available.

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Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Represent the number of separate advances.

No definition available.

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Represents the number of separate advances with the principal amount due at maturity.

No definition available.

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Data Type:	xbrli:integerItemType
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Amount as of the balance sheet date of final advances with principal paid monthly from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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- Details

Name:	us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresAbstract
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Data Type:	xbrli:stringItemType
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Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6479118&loc=d3e64650-112822

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22 (b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph 3(a)

-Article 9

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

Name:	us-gaap_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresCollateralPledged1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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States the weighted average interest rate applicable to the advances from the Federal Home Loan Bank outstanding as of the Balance Sheet date.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.13(3)(a))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Industry Guide

-Number 3

-Section VII

-Subsection 1

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- Details

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- Details

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Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.