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Nature of Operations and Significant Accounting Policies (Nature of Operations) (Details) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 30, 2015 employee | Oct. 31, 2015 employee | Nov. 30, 2014 employee | Dec. 25, 2015 USD ($) | Dec. 26, 2014 USD ($) | Dec. 27, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |  |  |  |  |
Number of weeks in fiscal reporting calendar |  |  |  | P52W | P52W | P52W
Number of weeks in fiscal quarter |  |  |  | P13W |  |
Cost method, maximum percentage |  |  |  | 20.00% |  |
Cash equivalents, maximum maturity period |  |  |  | 3 months |  |
Short-term investments, minimum maturity period |  |  |  | 3 months |  |
Short-term investments, maximum maturity period |  |  |  | 1 year |  |
Allowance for doubtful accounts |  |  |  | $ 37 | $ 41 |
Goodwill |  |  |  | 63 | 63 |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring charges incurred |  |  |  | 51 | 39 |
Workforce Reduction Plan [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions reduced | employee |  |  | 300 |  |  |
Workforce Reduction Plan [Member] | Employee Severance [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring charges incurred |  |  |  | 4 | 39 |
Erwin, Tennessee and Corbin, Kentucky Facilities [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring charges incurred |  |  |  | 19 | 0 |
Number of positions reduced | employee |  | 500 |  |  |  |
Union Agreement [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Number of positions reduced | employee | 300 |  |  |  |  |
Union Agreement [Member] | Employee Severance [Member] |  |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |  |
Restructuring charges incurred |  |  |  | $ 28 | $ 0 |

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