| Summary of Significant Accounting Policies - Revenues (Details) - USD ($) $ in Thousands | 9 Months Ended | |
|---|---|---|
| Sep. 27, 2018 | Sep. 28, 2017 | |
| Revenue from Contract with Customer [Abstract] | ||
| Number of days customer may return merchandise | 90 days | |
| Gift card breakage income | $ 1,340 | |
| Calculated under Revenue Guidance in Effect before Topic 606 [Member] | ||
| Revenue from Contract with Customer [Abstract] | ||
| Gift card breakage income | $ 568 | |
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- Definition The number of days a customer may return merchandise. No definition available. 
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- Definition For disclosures after the adoption of ASU 2016-04, the amount of breakage recognized related to unredeemed gift cards. Breakage occurs when a customer pays in advance of vendor performance and does not demand full performance for various reasons. No definition available. 
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- References No definition available. 
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- Details 
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