| **Non-Operating Income (Loss) (Tables)**     | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Nonoperating Income (Expense) [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
| Components of non-operating income (loss)    | The components of non-operating income (loss) were as follows: 2016 2015 2014       (In millions)Loss on prepayment of long-term debt (1)$— $(118) $—Gain on sales of businesses10 9 —Net income related to intellectual property matters— 1 4 $10 $(108) $4 (1)The loss in fiscal 2015 reflected charges associated with our optional redemption on May 27, 2015 of the entire outstanding $400 million principal amount of our 5.95% Notes due December 1, 2017 and the entire outstanding $350 million principal amount of our 6.375% Notes due June 15, 2019. |

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| - Definition
Components of non operating income (loss)
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