Debt - Interest expense (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jul. 02, 2022	Jul. 03, 2021	Jul. 02, 2022	Jul. 03, 2021
Interest expense related to the notes
Interest Expense, Total	$ 1,667	$ 6,486	$ 3,347	$ 17,810
Convertible Senior Notes
Interest expense related to the notes
Contractual interest expense	839	836	1,684	1,999
Amortization of debt discount		4,992		10,930
Amortization of debt issuance costs	497	374	994	892
Interest Expense, Total	$ 1,336	$ 6,202	$ 2,678	$ 13,821

Amount of the cost of borrowed funds accounted for as interest expense.

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Name:	us-gaap_InterestExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration