Quarterly report pursuant to Section 13 or 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 $)
3 Months Ended
Mar. 31, 2014
Restricted stock unit awards [Member]
 
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Stock Awards, Beginning Balance 356,589
Stock Awards, Granted 294,300
Stock Awards, Vested (34,585)
Stock Awards, Forfeited or expired (59,155)
Stock Awards, Ending Balance 557,149
Weighted-Average Grant Date Fair Value, Beginning Balance $ 12.06
Weighted-Average Grant Date Fair Value, Granted $ 11.79
Weighted-Average Grant Date Fair Value, Vested $ 12.38
Weighted-Average Grant Date Fair Value, Forfeited or expired $ 13.03
Weighted-Average Grant Date Fair Value, Ending Balance $ 11.79