Note 18 - Stock-based Compensation - Unrecognized Stock-based Compensation Expense (Details) $ in Thousands	Dec. 31, 2024 USD ($)
2025	$ 2,752
2026	2,427
2027	1,101
2028	594
2029	81
Total estimated expense	6,955
Stock Appreciation Rights (SARs) [Member]
2025	336
2026	286
2027	216
2028	126
2029	11
Total estimated expense	975
Restricted Stock [Member]
2025	1,478
2026	1,204
2027	885
2028	468
2029	70
Total estimated expense	4,105
Restricted Stock Units (RSUs) [Member]
2025	1
2026	0
2027	0
2028	0
2029	0
Total estimated expense	1
Performance Shares [Member]
2025	937
2026	937
2027	0
2028	0
2029	0
Total estimated expense	$ 1,874

Unrecognized cost of unvested share-based compensation awards due in fifth fiscal year following latest fiscal year.

No definition available.

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- Definition

Unrecognized cost of unvested share-based compensation awards due in fourth fiscal year following latest fiscal year.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

Unrecognized cost of unvested share-based compensation awards due in the first fiscal year following latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Unrecognized cost of unvested share-based compensation awards due in third fiscal year following latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Unrecognized cost of unvested share-based compensation awards due in second fiscal year following latest fiscal year.

+ References

No definition available.

+ Details

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

- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

+ Details

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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Period Type:

- Details

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Namespace Prefix:
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Period Type:

- Details

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Namespace Prefix:
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Period Type: