Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|---|---|
| Inventory Disclosure [Abstract] | ||||||
| Finished goods | $ 11,699 | $ 7,867 | ||||
| Semi-finished goods and work-in-process | 42,157 | 46,653 | ||||
| Raw materials | 8,091 | 7,846 | ||||
| Materials in-transit | 1,493 | 1,859 | ||||
| Less: inventory reserve | (5,297) | $ (7,966) | (7,177) | $ (14,997) | $ (17,246) | $ (16,033) |
| Inventories, net | $ 58,143 | $ 57,048 |