Commitments and contingencies - Schedule of Lease, Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 28, 2024	Sep. 30, 2023	Sep. 28, 2024	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 792	$ 1,041	$ 2,618	$ 3,120
Short-term lease cost	235	156	641	591
Amortization of finance lease assets	155	394	487	1,022
Interest on lease liabilities	216	230	654	596
Total lease cost	$ 1,398	$ 1,821	4,400	5,329
Cash paid for amounts included in measurement of lease liabilities:
Operating cash flows from operating leases			3,459	3,675
Operating cash flows from financing leases			654	644
Financing cash flows from finance leases			564	334
Right-of-use assets obtained in exchange for lease obligations:
Operating lease obligations			761	275
Financing lease obligations			$ 0	$ 15,567

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Right-Of-Use Asset Obtained In Exchange For Lease Liability

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Amount of interest expense on finance lease liability.

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Amount of cash outflow for principal payment on finance lease.

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Amount of short-term lease cost, excluding expense for lease with term of one month or less.

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