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Employee Defined Contribution Plan (Details) - 401(k) Plan [Member] - USD ($) $ in Millions | 12 Months Ended
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Dec. 27, 2020 | Dec. 29, 2019 | Dec. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Minimum age of employees to be eligible to participate in defined contribution plan | 21 years |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  |  | 50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  |  | 4.00%
Matching contribution expense | $ 2.5 | $ 3.0 | $ 0.9
Minimum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  | 100.00% |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  | 3.00% |
Maximum |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Defined Contribution Plan, Employer Matching Contribution, Percent of Match |  | 50.00% |
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay |  | 2.00% |

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- Definition Represents the minimum age of employees to be eligible to participate in the defined contribution plan. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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- Definition Percentage employer matches of the employee's percentage contribution matched. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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