Represents the amount of losses representing change in assets fair value disclosure allowances.

No definition available.

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- Definition

The fair value related to impaired financing receivables.

+ References

No definition available.

+ Details

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

- Definition

Represents the amount of losses representing change in specific allowances.

+ References

No definition available.

+ Details

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

- Definition

The fair value related to other real assets owned fair value disclosure.

+ References

No definition available.

+ Details

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

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260

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Note 16 - Assets and Liabilities Measured and Reported at Fair Value - Assets Measured at Fair Value on a Non-recurring Basis (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Other real estate owned	$ 22	$ 109
Fair Value, Nonrecurring [Member]
Impaired loans	369		$ 925
Impaired loans	(3)	(1,711)
Other real estate owned	239		239
Other real estate owned
Assets, Fair Value Disclosure	608		1,164
Total	(3)	$ (1,711)
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 1 [Member]
Impaired loans
Other real estate owned
Assets, Fair Value Disclosure
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 2 [Member]
Impaired loans
Other real estate owned
Assets, Fair Value Disclosure
Fair Value, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Impaired loans	369		925
Other real estate owned	239		239
Assets, Fair Value Disclosure	$ 608		$ 1,164