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EMPLOYEE BENEFIT PLANS - Defined Contribution Plan (Details) - USD ($) | 12 Months Ended
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Dec. 26, 2018 | Dec. 27, 2017 | Dec. 28, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer contributions | $ 509,000 | $ 389,000 | $ 257,000
Defined Contribution Plan, Initial Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer matching contribution percentage | 100.00% |  |
Employer matching contribution as a percent of employees' gross pay | 3.00% |  |
Defined Contribution Plan, Additional Contribution |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer matching contribution percentage | 50.00% |  |
Employer matching contribution as a percent of employees' gross pay | 3.00% |  |
Defined Contribution Plan, Additional Contribution | Maximum |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer matching contribution as a percent of employees' gross pay | 5.00% |  |

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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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- 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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- Details
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- Details
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- Details
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