Note 12 - Securities Sold Under Agreements to Repurchase (Details Textual) - USD ($) $ in Thousands	Mar. 07, 2022	May 31, 2021
Commonwealth [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Securities Sold under Repurchase Agreement	$ 66,220
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