Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 28, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Reserves for accounts receivable	$ 2,235	$ 1,821
Common stock, par value	$ 0.002	$ 0.002
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	173,047,000	172,440,000