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RESTRUCTURING AND ASSET IMPAIRMENTS - Narrative (Details) - USD ($) $ in Thousands | Mar. 27, 2021 | Dec. 26, 2020 | Mar. 28, 2020 | Dec. 28, 2019
--- | --- | --- | --- | ---
Restructuring Cost and Reserve [Line Items] |  |  |  |
Severance and other personnel related costs liability and lease obligation liabilities | $ 2,221 | $ 5,816 | $ 2,531 | $ 6,406
Severance and Transition Costs | Accrued Compensation and Accrued Liabilities |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Severance and other personnel related costs liability and lease obligation liabilities | $ 2,200 |  | 2,400 |
Severance and Transition Costs | Other Long-Term Liabilities |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |
Severance and other personnel related costs liability and lease obligation liabilities |  |  | $ 100 |

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