Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 04, 2021	Dec. 31, 2020	Mar. 31, 2020
Condensed Consolidated Balance Sheets
Accumulated amortization of intangible assets	$ 244	$ 238	$ 23,824
Preferred stock, par value (in dollars per share)	$ 1.00	$ 1.00	$ 1.00
Common stock, par value (in dollars per share)	$ 0.025	$ 0.025	$ 0.025
Common stock, shares authorized (in shares)	280,000,000	280,000,000	280,000,000
Common stock, shares issued (in shares)	85,369,434	85,075,901	84,666,505
Common stock, shares outstanding (in shares)	85,369,434	85,075,901	84,666,505