Equity-based compensation - Narrative (Details) - USD ($)	3 Months Ended
Mar. 30, 2024	Apr. 01, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation	$ 2,591,000
Unamortized compensation expense, options	5,211,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized compensation expense, RSUs	$ 8,159,000
Compensation expense net yet amortized, period for recognition	1 year 8 months 15 days
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	2 years 1 month 24 days
Expiration period	10 years
Weighted-average fair value of stock options granted (in dollars per share)	$ 2.26
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
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)	1,519,604
Equity compensation		$ 128,000
Number of shares issued (in shares)	0	222,076
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Income tax benefit	$ 0	$ 430,000
2021 and 2023 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity compensation		$ 1,718,000
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock closing price, (in dollars per share)	$ 5.20
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)	19,564,333
Number of shares available to be awarded (in shares)	9,119,667
Common Class A \| 2023 Retention Equity Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized to be awarded (in shares)	600,000
Number of shares available to be awarded (in shares)	80,700

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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