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ORGANIZATION AND OPERATIONS OF THE COMPANY - Fiscal Years (Details) - item | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 27, 2019 | Sep. 28, 2018 | Jun. 29, 2018 | Mar. 30, 2018 | Dec. 27, 2019 | Dec. 28, 2018 | Dec. 29, 2017
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Number of VIE |  |  |  |  | 1 |  |
Length of fiscal period |  | 91 days | 91 days | 91 days | 364 days | 364 days | 364 days
Minimum |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Length of fiscal period | 91 days |  |  |  | 364 days |  |
Maximum |  |  |  |  |  |  |
Summary of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |
Length of fiscal period | 98 days |  |  |  | 371 days |  |

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- Definition Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter. + References No definition available. + Details
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