Debt - Interest expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2023	Jul. 02, 2022	Jul. 01, 2023	Jul. 02, 2022
Interest expense related to the notes
Interest Expense, Total	$ 1,596	$ 1,667	$ 3,252	$ 3,347
Convertible Senior Notes
Interest expense related to the notes
Contractual interest expense	648	839	1,493	1,684
Amortization of debt issuance costs	436	497	960	994
Interest Expense, Total	$ 1,084	$ 1,336	$ 2,453	$ 2,678