Annual report pursuant to Section 13 and 15(d)

Common Stock - Summary of Restricted Stock Unit Award Activity (Detail)

v2.4.0.8
Common Stock - Summary of Restricted Stock Unit Award Activity (Detail) (Restricted stock unit awards [Member], USD $)
12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Restricted stock unit awards [Member]
     
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Number of Shares, Beginning Balance 172,085    
Number of Shares, Granted 255,895 180,085   
Number of Shares, Vested (50,773)    
Number of Shares, Forfeited or expired (20,618) (8,000)  
Number of Shares, Ending Balance 356,589 172,085  
Weighted-Average Grant Date Fair Value, Beginning Balance $ 13.01      
Weighted-Average Grant Date Fair Value, Granted $ 11.64 $ 13.01   
Weighted-Average Grant Date Fair Value, Vested $ 12.95      
Weighted-Average Grant Date Fair Value, Forfeited or expired $ 12.51 $ 13.00   
Weighted-Average Grant Date Fair Value, Ending Balance $ 12.06 $ 13.01