Estimated performance period which is required for the equity-based payment award.

No definition available.

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

- Definition

The number of shares most likely to be granted with the vesting of the awards.

+ References

No definition available.

+ Details

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

- Definition

Current market price at which the awards granted.

+ References

No definition available.

+ Details

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

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Stock-Based Compensation (Details 3) (USD $)	81 Months Ended	3 Months Ended							9 Months Ended
Stock-Based Compensation (Details 3) (USD $)	Sep. 30, 2013	Sep. 30, 2013 SARs	Jun. 30, 2013 SARs	Mar. 31, 2013 SARs	Sep. 30, 2013 Restricted stock	Jun. 30, 2013 Restricted stock	Mar. 31, 2013 Restricted stock	Mar. 31, 2013 Restricted stock units (RSUs) Executive Officer	Sep. 30, 2013 Restricted stock units (RSUs) Executive Officer	Sep. 30, 2012 Restricted stock units (RSUs) Executive Officer
Stock-based compensation
Awards granted (in shares)		0	0	53,598	0	0	55,275
Weighted average current market price (in dollars per share)				$ 22.89			$ 22.93
Performance period								3 years
Fair value of awards granted (in dollars per share)				$ 3.61					$ 20.38	$ 20.57
Number of shares most likely to vest, based on most recent analysis									62,389
Stock options granted (in shares)	0