Impairment and closure (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | ||||
|---|---|---|---|---|---|---|
Dec. 25, 2016 |
Sep. 25, 2016 |
Dec. 27, 2015 |
Dec. 25, 2016 |
Dec. 27, 2015 |
Dec. 28, 2014 |
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| Impairment and Closure Costs [Abstract] | ||||||
| Impairment and closure costs | $ 1,127 | $ 390 | $ 4,360 | $ 1,517 | $ 4,360 | $ 0 |
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- Definition Impairment and Closure Costs [Abstract] No definition available.
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- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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