Premises, Equipment and Leasehold Improvements (Details Narrative)	9 Months Ended
Sep. 30, 2012
Buildings
Estimated useful life (in years)	40 years
Maximum \| Equipment
Estimated useful life (in years)	15 years
Minimum \| Equipment
Estimated useful life (in years)	3 years

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale.

No definition available.

Name:	bksc_PropertyPlantAndEquipmentUsefulLife1
Namespace Prefix:	bksc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration