Name:	sybt_FederalHomeLoanBankAdvancesGeneralDebtObligationsWeightedAverageInterestRate
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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 after the eighth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearEight
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 fifth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearFive
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 fourth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearFour
Namespace Prefix:	sybt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateOfAmountsDueInYearNine
Namespace Prefix:	sybt_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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
Balance Type:	na
Period Type:	instant

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_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

No definition available.

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

Amount of Federal Home Loan Bank advances maturing in the ninth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryDueEightToNineYearsFromBalanceSheetDate
Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of Federal Home Loan Bank advances maturing in the twelve fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryDueElevenToTwelveYearsFromBalanceSheetDate
Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of Federal Home Loan Bank advances maturing in the tenth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryDueNineToTenYearsFromBalanceSheetDate
Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of Federal Home Loan Bank advances maturing in the Eighth fiscal year following the latest fiscal year.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryDueSevenToEightYearsFromBalanceSheetDate
Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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.

Name:	us-gaap_AdvancesFromFederalHomeLoanBanks
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fifth 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: 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

Name:	us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromFourToFiveYearsOfBalanceSheetDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in the fourth 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.

Name:	us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryDueFromThreeToFourYearsOfBalanceSheetDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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.

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 FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601