v2.3.0.9
DOCUMENT AND ENTITY INFORMATION (USD $)
12 Months Ended
Dec. 31, 2011
Mar. 20, 2012
Jun. 30, 2011
Entity Registrant Name POTOMAC BANCSHARES INC    
Entity Central Index Key 0000925173    
Current Fiscal Year End Date --12-31    
Entity Filer Category Smaller Reporting Company    
Trading Symbol ptbs    
Entity Common Stock, Shares Outstanding   3,390,178  
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2011
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2011    
Entity Well-Known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 19,207,285