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Major Customers and Suppliers - Additional Information (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 26, 2020 | Sep. 28, 2019 | Sep. 26, 2020 | Sep. 28, 2019 | Dec. 28, 2019
Revenue | One Customers |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk percentage | 30.00% | 16.00% |  | 11.00% |
Revenue | Two Customers |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk percentage |  |  | 32.00% |  |
Accounts Receivable | Two Customers |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk percentage |  |  | 38.00% |  |
Accounts Receivable | Three Customers |  |  |  |  |
Concentration Risk [Line Items] |  |  |  |  |
Concentration risk percentage |  |  |  |  | 49.00%

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