|**Unearned ESOP Shares (Tables)**                                             | 12 Months Ended                                                                                                                                                                                                                                                                                                                                 
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|**Disclosure of Compensation Related Costs, Share-based Payments [Abstract]** |                                                                                                                                                                                                                                                                                                                                                 
|Analysis of ESOP Shares Held in Suspense and Its Fair Value                   | The following is an analysis of ESOP shares held in suspense and the fair value of those shares as of December 31:20122011(dollars in thousands)Shares in suspense, beginning of the year104,661237,106Shares allocated(104,661)(132,445)Shares acquired——Shares in suspense, end of the year—104,661Fair market value of shares in suspense—550
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|                                                                              | 2012                                                                                                                                                                                                                                                                                                                                            
|                                                                              | (dollars in thousands)                                                                                                                                                                                                                                                                                                                          
|Shares in suspense, beginning of the year                                     | 104,661                                                                                                                                                                                                                                                                                                                                         
|Shares allocated                                                              | (104,661                                                                                                                                                                                                                                                                                                                                        
|Shares acquired                                                               | —                                                                                                                                                                                                                                                                                                                                               
|Shares in suspense, end of the year                                           | —                                                                                                                                                                                                                                                                                                                                               
|Fair market value of shares in suspense                                       | —                                                                                                                                                                                                                                                                                                                                               
|Interest Paid on ESOP Loan and Dividends Received on Unallocated Shares       | Interest paid on the ESOP loan and dividends received on unallocated shares for the year ended December 31 were:20122011(dollars in thousands)Interest paid on ESOP loan$13$38Dividends on unallocated shares1932                                                                                                                               
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|                                                                              | 2012                                                                                                                                                                                                                                                                                                                                            
|                                                                              | (dollars in thousands)                                                                                                                                                                                                                                                                                                                          
|Interest paid on ESOP loan                                                    | $                                                                                                                                                                                                                                                                                                                                               
|Dividends on unallocated shares                                               | 19                                                                                                                                                                                                                                                                                                                                              

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