Note 9 - Securities Sold Under Agreements to Repurchase (Details Textual) $ in Thousands	Jun. 01, 2021 USD ($)
Kentucky Bancshares [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Securities Sold under Repurchase Agreement	$ 11,360

Amount of securities sold under agreement to repurchase assumed at the acquisition date.

No definition available.

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