Shareholders' Equity (Tables)
12 Months Ended
Dec. 31, 2013
Equity [Abstract]  
Summary of Actual Capital Amount and Well Capitalized Total Risk-Based, Tier I Risk-Based, and Tier I Leverage Ratios

Actual capital amounts, as well as required and well capitalized total risk-based, Tier I risk-based, and Tier I leverage ratios as of December 31, 2013 and 2012, for the Company and the Bank were as follows:

 

     2013  
     Actual     Adequacy
Purposes
    To Be Well
Capitalized Under
Prompt
Corrective
Action Provisions
 
     Amount      Ratio     Amount      Ratio     Amount      Ratio  
     (Dollars in Thousands)  

Total Capital (to Risk Weighted Assets):

               

United Security Bancshares, Inc.

   $ 64,842         19.20   $ 27,012         8.00     N/A         N/A   

First United Security Bank

     65,304         19.34     27,012         8.00   $ 33,765         10.00

Tier I Capital (to Risk Weighted Assets):

               

United Security Bancshares, Inc.

     60,557         17.93     13,506         4.00     N/A         N/A   

First United Security Bank

     61,019         18.07     13,506         4.00     20,259         6.00

Tier I Leverage (to Average Assets):

               

United Security Bancshares, Inc.

     60,557         10.88     16,698         3.00     N/A         N/A   

First United Security Bank

     61,019         10.97     16,691         3.00     27,819         5.00

 

     2012  
     Actual     Adequacy
Purposes
    To Be Well
Capitalized Under
Prompt
Corrective
Action Provisions
 
     Amount      Ratio     Amount      Ratio     Amount      Ratio  
     (Dollars in Thousands)  

Total Capital (to Risk Weighted Assets):

               

United Security Bancshares, Inc.

   $ 63,957         17.05   $ 30,008         8.00     N/A         N/A   

First United Security Bank

     64,422         17.17     30,008         8.00   $ 37,510         10.00

Tier I Capital (to Risk Weighted Assets):

               

United Security Bancshares, Inc.

     59,088         15.75     15,004         4.00     N/A         N/A   

First United Security Bank

     59,553         15.88     15,004         4.00     22,506         6.00

Tier I Leverage (to Average Assets):

               

United Security Bancshares, Inc.

     59,088         10.51     16,873         3.00     N/A         N/A   

First United Security Bank

     59,553         10.60     16,862         3.00     28,104         5.00