Net Income (Loss) per Share of Common Stock - Basic and Diluted Net Income (Loss) per Share of Common Stock (Detail) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Earnings Per Share [Abstract]                    
Net income (loss) from continuing operations         $ 811 $ (3,670) $ (1,074) $ (2,330) $ (26,470) $ (6,263)
Income from discontinued operations, net of tax (Note 5)         0 1,610 (7,704) 14,512 0 8,418
Net (loss) income $ 2,903 $ (3,413) $ (22,979) $ (2,981) $ 811 $ (2,060) $ (8,778) $ 12,182 $ (26,470) $ 2,155
Shares used in computing net income (loss) per share of common stock:                    
Basic (shares)                 16,709 17,239
Diluted (shares)                 16,709 17,296
Basic:                    
Continuing operations (usd per share)                 $ (1.58) $ (0.36)
Discontinued operations (usd per share)                 0.00 0.49
Total (usd per share)                 (1.58) 0.13
Diluted:                    
Continuing operations (usd per share)                 (1.58) (0.36)
Discontinued operations (usd per share)                 0.00 0.49
Total (usd per share)                 $ (1.58) $ 0.13