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

Represent the number of separate advances.

No definition available.

Name:	sybt_FederalHomeLoanBankNumberOfSeparateAdvances
Namespace Prefix:	sybt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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

No definition available.

Name:	sybt_FederalHomeLoanBankNumberOfSeparateAdvancesPrincipalDueAtMaturity
Namespace Prefix:	sybt_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

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.

Name:	sybt_FinalAdvancesFromFederalHomeLoanBanksPrincipalPaidMonthly
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.

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

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

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 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 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 3: 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