Property and Equipment - Long-lived assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Jan. 01, 2022
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	$ 45,582	$ 53,612
United States
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	38,495	44,340
United Kingdom
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	4,943	6,491
Other
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	$ 2,144	$ 2,781

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant