Stockholders' Equity - Summary of Stock Option Activity (Detail) - USD ($)
$ / shares in Units, $ in Thousands |
12 Months Ended |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
| Number of Shares, Outstanding at beginning of period |
3,196,100
|
4,192,927
|
4,279,919
|
| Number of Shares, Granted |
684,629
|
|
|
| Number of Shares, Exercised |
(235,480)
|
(1,332,563)
|
(115,667)
|
| Number of Shares, Forfeitures |
(247,720)
|
(84,744)
|
(250,119)
|
| Number of Shares, Outstanding at end of period |
3,397,529
|
3,196,100
|
4,192,927
|
| Weighted Average Exercise Price Per Share, Outstanding at beginning of period |
$ 4.32
|
$ 3.82
|
$ 3.70
|
| Weighted average Exercise Price Per Share, Exercised |
3.52
|
3.48
|
3.25
|
| Weighted Average Exercise Price Per Share, Forfeitures |
12.65
|
5.26
|
2.89
|
| Weighted Average Exercise Price Per Share, Outstanding at end of period |
$ 5.42
|
$ 4.32
|
$ 3.82
|
| Aggregate Intrinsic Value, Outstanding at beginning of period |
$ 22,881
|
$ 9,146
|
$ 4,572
|
| Aggregate Intrinsic Value, Outstanding at end of period |
$ 3,124
|
$ 22,881
|
$ 9,146
|
| Officers and Directors [Member] |
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
| Number of Shares, Granted |
|
|
55,659
|
| Weighted Average Exercise Price Per Share, Granted |
|
|
$ 5.39
|
| Others [Member] |
|
|
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
|
|
|
| Number of Shares, Granted |
684,629
|
420,480
|
223,135
|
| Weighted Average Exercise Price Per Share, Granted |
$ 8.14
|
$ 13.86
|
$ 4.47
|