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Equity-based compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Apr. 01, 2023	Apr. 02, 2022	Mar. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax expense (benefit)	$ (146)	$ (5,132)
Unamortized compensation expense, options	9,614
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation	1,718	4,731
Income tax expense (benefit)	$ (430)	1,225
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock closing price, (in dollars per share)			$ 1.07
Common Class A \| 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be awarded (in shares)	11,278,656
Number of shares available to be awarded (in shares)	2,762,266
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense, RSUs	$ 2,265
Compensation expense net yet amortized, period for recognition	2 years 6 months
RSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
RSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense net yet amortized, period for recognition	3 years 9 months 10 days
Expiration period	10 years
Weighted-average fair value of stock options granted (in dollars per share)	$ 1.10
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	2 years
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available to be awarded (in shares)	1,181,830
Equity compensation	$ 128	$ 158
Number of shares issued (in shares)	222,076	48,993