Name:	sybt_Note11StockBasedCompensationDetailsStockOptionandSARsActivityLineItems
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Amount of difference between the fair value of the underlying shares on dates of exercise and exercise price of exercised stock options and stock appreciation rights.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsExercisableIntrinsicValue
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The weighted average price at which option and stock appreciation rights holders acquired shares when converting their stock options and stock appreciation rights into shares under the plan during the reporting period.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsExercisesInPeriodWeightedAverageExercisePrice
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The weighted average fair value of exercised stock options and stock appreciation rights under the plan.

No definition available.

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Amount of difference between the fair value of the underlying shares and exercise price of stock options and stock appreciation rights granted during the period.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Gross number of share stock options (or share units) and stock appreciation rights granted during the period.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsGrantsInPeriodGross
Namespace Prefix:	sybt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The weighted average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on stock options and stock appreciation rights awarded under the plans during the reporting period.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsGrantsInPeriodWeightedAverageExercisePrice
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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The weighted average fair value of granted stock options and stock appreciation rights under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The number of shares reserved for issuance under stock option agreements and stock appreciation rights agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsOutstandingNumber
Namespace Prefix:	sybt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsOutstandingWeightedAverageExercisePrice
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The weighted average fair value of shares reserved for issuance under stock option and stock appreciation right agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including unvested stock options and stock appreciation rights.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsOutstandingWeightedAverageGrantDateFairValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The weighted average period between the balance sheet date and expiration date of all awards outstanding under the plans.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsOutstandingWeightedAverageRemainingContractualTerm
Namespace Prefix:	sybt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of unvested stock options and stock appreciation rights outstanding as of the balance sheet date.

No definition available.

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

The number of non-vested stock (or unit) options and stock appreciation rights that validly exist and are outstanding as of the balance sheet date.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsUnvestedNumber
Namespace Prefix:	sybt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The weighted-average exercise price as of the balance sheet date for outstanding stock options and stock appreciation rights that remain unvested under the stock option plan or the stock appreciation rights plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsUnvestedWeightedAverageExercisePrice
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The weighted average fair value of all unvested options and stock appreciation rights outstanding under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsUnvestedWeightedAverageGrantDateFairValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The weighted average period between the balance sheet date and expiration date of all unvested options and stock appreciation rights outstanding under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsUnvestedWeightedAverageRemainingContractualTerm
Namespace Prefix:	sybt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options and stock appreciation rights outstanding and currently exercisable as of the balance sheet date.

No definition available.

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

The weighted average fair value of all vested portions of options and stock appreciation rights outstanding and currently exercisable (or convertible) under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedAndExercisableInPeriodWeightedAverageFairValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The number of shares into which fully or partially vested stock options (or share units) and stock appreciation rights outstanding as of the balance sheet date can be currently converted under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedAndExercisableNumber
Namespace Prefix:	sybt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options and stock appreciation rights outstanding under the plan as of the balance sheet date.

No definition available.

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

The weighted average period between the balance sheet date and expiration date of all vested portions of options and stock appreciation rights outstanding and currently exercisable (or convertible) under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedAndExercisableOutstandingWeightedAverageRemainingContractualTerm
Namespace Prefix:	sybt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of stock options and stock appreciation rights outstanding and currently exercisable under the stock option plan or the stock appreciation rights plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedAndExercisableWeightedAverageExercisePrice
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

The number of shares under stock options and stock appreciation rights that were vested during the reporting period as a result of the occurrence of an event specified in contractual agreements pertaining to the stock option plan or the stock appreciation rights plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedInPeriod
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Data Type:	xbrli:sharesItemType
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Period Type:	duration

Amount of difference between the fair value of the underlying shares and exercise price of stock options and stock appreciation rights vested during the period.

No definition available.

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

The weighted average fair value of awards vested stock options and stock appreciation rights under the plan.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedInPeriodIntrinsicValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The weighted average exercise price of stock options and stock appreciation rights vested during the reporting period.

No definition available.

Name:	sybt_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndSARsVestedInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

The exercise price for purposes of disclosing shares potentially issuable under outstanding stock option awards and stock appreciation rights under the plans.

No definition available.

Name:	sybt_ShareBasedCompensationSharesAuthorizedUnderStockOptionAndSARsPlansExercisePrice
Namespace Prefix:	sybt_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

Number of share options (or share units) and stock appreciation rights exercised during the period.

No definition available.

Name:	sybt_StockIssuedDuringPeriodSharesStockOptionsAndSARsExercised
Namespace Prefix:	sybt_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

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