| Outstanding Restricted Shares Issued to Non-employee Directors (Detail) (Restricted Stock) | 12 Months Ended | 
|---|---|
| Dec. 31, 2013 | |
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
| Awards expected to vest by period | 43,840 | 
| 2014 | |
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
| Awards expected to vest by period | 19,445 | 
| 2015 | |
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
| Awards expected to vest by period | 15,245 | 
| 2016 | |
| Share Based Compensation Arrangement By Share Based Payment Award [Line Items] | |
| Awards expected to vest by period | 9,150 | 
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options vested and expected to vest number. No definition available. 
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