Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 26, 2020	Dec. 28, 2019
Statement of Financial Position [Abstract]
Accounts Receivable, Allowance for Credit Loss, Current	$ 222	$ 222
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 287,141	$ 273,001
Common stock, par value (In dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (In shares)	250,000,000	250,000,000
Common stock, shares issued (In shares)	77,383,494	75,764,990
Common stock, shares outstanding (In shares)	77,383,494	75,764,990