Net Loss per Share - Schedule of Antidilutive Unvested RSUs Excluded from Computation of Net Loss per Share (Details) - Restricted Stock Units (RSUs) - shares |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 28, 2026 |
Jun. 29, 2025 |
Jun. 28, 2026 |
Jun. 29, 2025 |
|
| KKI | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities excluded from computation of net loss per share | 11,930,000 | 8,513,000 | 11,930,000 | 8,513,000 |
| KK Australia | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities excluded from computation of net loss per share | 0 | 74,000 | 0 | 74,000 |
| KK Mexico | ||||
| Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||||
| Antidilutive securities excluded from computation of net loss per share | 0 | 18,000 | 0 | 18,000 |