Balance Sheet Items - Schedule of Property and Equipment Acquired under Capital Leases (Detail) - USD ($) $ in Thousands |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Building [Member] | ||
| Capital Leased Assets [Line Items] | ||
| Building and Production equipment | $ 35 | $ 35 |
| Less accumulated depreciation | (35) | 0 |
| Building and Production equipment, net | 0 | 35 |
| Production equipment [Member] | ||
| Capital Leased Assets [Line Items] | ||
| Building and Production equipment | 127 | 389 |
| Less accumulated depreciation | (127) | (389) |
| Building and Production equipment, net | $ 0 | $ 0 |