13. Deposits and other assets (Details) - USD ($) $ in Thousands |
Mar. 31, 2018 |
Dec. 30, 2017 |
|---|---|---|
| Assets, Noncurrent [Abstract] | ||
| Deposits | $ 408 | $ 411 |
| Other | 100 | 107 |
| Total other assets | $ 508 | $ 518 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer. No definition available.
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| X | ||||||||||
- Definition Amount of noncurrent assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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