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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands | Sep. 28, 2019 | Jan. 01, 2019 | Dec. 30, 2018 | Dec. 29, 2018
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New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Operating lease assets | $ 53,689 |  |  | $ 0
Operating lease liability | 53,799 |  |  |
Cumulative impact, deferred gains |  |  | $ 1,291 |
ASU 2016-02 |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Operating lease assets |  |  | $ 57,500 |
Operating lease liability |  | $ 57,500 |  |
Cumulative impact, deferred gains |  | $ 1,700 |  |
Accounts Payable |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |
Outstanding checks and electronic payments | $ 39,800 |  |  | $ 17,400

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