Note 23 - Mortgage Banking Activities - Activity in Mortgage Loans Held for Sale (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Balance, beginning of period:	$ 6,056	$ 2,606	$ 8,614
Origination of mortgage loans held for sale	114,773	105,912	129,193
Loans held for sale acquired	0	0	3,559
Proceeds from the sale of mortgage loans held for sale	(116,974)	(104,152)	(139,281)
Net gain on sale of mortgage loans held for sale	2,431	1,690	521
Balance, end of period	$ 6,286	$ 6,056	$ 2,606

Amount of loan receivable held-for-sale acquired through business acquisition.

No definition available.

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

- Definition

The proceeds from sale of mortgage loans held for sale at fair value.

+ References

No definition available.

+ Details

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Namespace Prefix:	sybt_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477409/944-310-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477409/944-310-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477363/944-310-50-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount, after valuation allowance, of financing receivable held for sale and not part of disposal group. Excludes loan covered under loss sharing agreement and loan classified as investment in debt security.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477011/948-310-45-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after allowance for credit loss, of addition to financing receivable held for sale that is not part of disposal group.

+ References

+ Details

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