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Stock-Based Compensation - Summary of Changes in Nonvested Restricted Stock Awards (Detail) (USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]      
Nonvested at beginning of period, Shares 49,574    
Granted, Shares 31,500 26,900 17,900
Forfeited, Shares (525)    
Vested, Shares (18,473)    
Nonvested at end of period, Shares 62,076 49,574  
Nonvested at beginning of period, Weighted-average Grant Date Fair Value $ 15.37    
Granted, Weighted-average Grant Date Fair Value $ 17.10    
Forfeited, Weighted-average Grant Date Fair Value $ 16.44    
Vested, Weighted-average Grant Date Fair Value $ 15.33    
Nonvested at end of period, Weighted-average Grant Date Fair Value $ 16.25 $ 15.37