| **Quarterly Financial And Market Information (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Quarterly Financial Data [Abstract]**                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Summary Of Quarterly Financial And Market Information   |  Quarter Ended YearEnded(In millions, except per share data)June 30 September 30 December 31 March 31 Fiscal 2016 Consolidated         Net revenue$1,203 $815 $1,070 $1,308 $4,396Gross profit1,030 406 524 1,082 3,042Operating income (loss)512 (119) (31) 536 898Net income (loss)442(140)(45)899(a) 1,156Common Stock         Earnings (loss) per share — Basic$1.42 $(0.45) $(0.14) $2.93 $3.73Earnings (loss) per share — Diluted$1.32 $(0.45) $(0.14) $2.79 $3.50Common stock price per share         High$68.00 $75.16 $76.77 $70.83 $76.77Low$56.03 $63.43 $65.04 $55.50 $55.50Fiscal 2015 Consolidated         Net revenue$1,214 $990 $1,126 $1,185 $4,515Gross profit847 563 725 951 3,086Operating income362 24 162 400 948Net income3353142395875Common Stock         Earnings per share — Basic$1.07 $0.01 $0.46 $1.27 $2.81Earnings per share — Diluted$1.04 $0.01 $0.44 $1.19 $2.69Common stock price per share         High$37.15 $38.42 $48.33 $58.24 $58.24Low$26.67 $33.31 $32.62 $45.96 $26.67(a)Net income includes an income tax benefit recorded in the fourth quarter of fiscal year 2016 for the reversal of a significant portion of our deferred tax valuation allowance. |

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| - References
No definition available.
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| - Definition
Tabular disclosure of the quarterly financial data in the annual financial statements. The disclosure includes financial information for each fiscal quarter for the current and previous year, including revenues, gross profit, income (loss) before extraordinary items and cumulative effect of a change in accounting principle and earnings per share data.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 270 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a)-(j) -URI http://asc.fasb.org/extlink&oid=51825399&loc=d3e1280-108306
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