CONSOLIDATED BALANCE SHEETS (unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Statement of Financial Position [Abstract]
Accumulated depreciation	$ 136,863	$ 141,367
Preferred stock, par value per share (in dollars per share)	$ 0.01000	$ 0.01000
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share (in dollars per share)	$ 0.01000	$ 0.01000
Common stock, shares authorized	300,000,000	300,000,000
Common stock, shares issued	132,536,000	129,728,000
Common stock, shares outstanding	132,536,000	129,728,000