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Description of Business and Summary of Significant Accounting Policies Pension and Other Post-Retirement Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 26, 2015 | Dec. 27, 2014
Change in Discount Rate Methodology |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Increase (decrease) in pension and postretirement obligations |  | $ 5.5
US Pension Plan | Change in Mortality Tables |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |
Increase (decrease) in pension and postretirement obligations | $ 3.3 | $ 7.9

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- Definition The increase (decrease) during the reporting period in the amount due to fund pension and non-pension benefits to employees, retired and disabled former employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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