Income Taxes (Details 3) - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Dec. 30, 2018  | 
Dec. 31, 2017  | 
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| Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] | ||
| Beginning of year | $ 287 | $ 170 | 
| Increase due to current year tax positions | 82 | 172 | 
| Due to decrease to a position taken in a prior year | (7) | (2) | 
| Settlements | (21) | (11) | 
| Reductions related to lapses | (37) | (42) | 
| End of year | $ 304 | $ 287 | 
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available. 
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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