Quarterly report pursuant to Section 13 or 15(d)

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

v3.4.0.3
Common Stock - Summary of Restricted Stock Unit Award Activity (Detail) - Restricted Stock Unit [Member]
3 Months Ended
Mar. 31, 2016
$ / shares
shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Number of Shares, Beginning Balance | shares 640,759
Number of Shares, Settled | shares (101,228)
Number of Shares, Forfeited or expired | shares (38,441)
Number of Shares, Ending Balance | shares 501,090
Weighted-Average Grant Date Fair Value, Beginning Balance | $ / shares $ 4.92
Weighted-Average Grant Date Fair Value, Settled | $ / shares 7.28
Weighted-Average Grant Date Fair Value, Forfeited or expired | $ / shares 4.23
Weighted-Average Grant Date Fair Value, Ending Balance | $ / shares $ 4.50