Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Apr. 01, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Reserves for accounts receivable | $ 1,664 | $ 1,568 |
| Common stock, par value | $ 0.002 | $ 0.002 |
| Common stock, shares authorized | 200,000,000 | 200,000,000 |
| Common stock, shares issued | 172,948,000 | 173,507,000 |
| Common stock, shares outstanding | 172,948,000 | 173,507,000 |