Property and Equipment - Long-lived assets (Details) - USD ($) $ in Thousands	Jan. 01, 2022	Jan. 02, 2021
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	$ 53,612	$ 62,878
United States
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	44,340	52,040
United Kingdom
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	6,491	7,534
Other
Long-lived assets by geographic location
Long-lived assets (property and equipment, net)	$ 2,781	$ 3,304

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