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

States the average interest rate applicable to Federal Home Loan Bank advances due in one to four years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due in six to nine years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due ten to twelve years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due in two to five years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due nine years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due in one year from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due six years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due ten years from the balance sheet date.

No definition available.

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

States the average interest rate applicable to Federal Home Loan Bank advances due in eleven to thirteen years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing eleven to thirteen years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in five to eight years of the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in one to four years of the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in six years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing nine years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing in six to nine years from balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing ten to twelve years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing ten years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing two to five years from the balance sheet date.

No definition available.

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

Amount of advances from Federal Home Loan Bank (FHLBank) maturing one year from the balance sheet date.

No definition available.

Name:	sybt_FederalHomeLoanBankAdvancesMaturitiesSummaryDueYearOne
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

States the interest rate applicable to Federal Home Loan Bank advances 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 470
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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_FederalHomeLoanBankAdvancesGeneralDebtObligationsDisclosuresInterestRateAtPeriodEnd
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

The weighted average interest rate applicable to the Federal Home Loan Bank advances which are due from four to five years 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

Name:	us-gaap_FederalHomeLoanBankAdvancesMaturitiesSummaryAverageInterestRateFourToFiveYearsFromBalanceSheetDate
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
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
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