Note 8 - Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits, Including Penalties and Interest	$ 42	$ 42

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns, including penalties and interest accrued.

No definition available.

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