| **Earnings Per Share**                           | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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| **Earnings Per Share Reconciliation [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Earnings (Loss) Per Share                        | (13) EARNINGS PER SHAREThe following table summarizes the computations of basic earnings per share (“Basic EPS”) and diluted earnings per share (“Diluted EPS”). Basic EPS is computed as net income divided by the weighted-average number of common shares outstanding for the period. Diluted EPS reflects the potential dilution that could occur from common shares issuable through stock-based compensation plans including stock options, restricted stock, restricted stock units, ESPP purchase rights, warrants, and other convertible securities using the treasury stock method. Three months ended June 30, (In millions, except per share amounts)2017 2016Net income$644 $440Shares used to compute earnings per share:   Weighted-average common stock outstanding — basic309 301Dilutive potential common shares related to stock award plans and from assumed exercise of stock options4 4Dilutive potential common shares related to the Convertible Notes (a)— 2Dilutive potential common shares related to the Warrants (a)— 8Weighted-average common stock outstanding — diluted313 315Earnings per share:   Basic$2.08 $1.46Diluted$2.06 $1.40For the three months ended June 30, 2017 and 2016, an immaterial amount of stock options, restricted stock units and market-based restricted stock units were excluded from the treasury stock method computation of diluted shares as their inclusion would have had an antidilutive effect. Our performance-based restricted stock units, which are considered contingently issuable shares, are also excluded from the treasury stock method computation because the related performance-based milestones were not achieved as of the end of the reporting period.(a)See Note 10 - Financing Arrangements in our Annual Report on Form 10-K for the fiscal year ended March 31, 2017, for additional information regarding the potential dilutive shares related to our Convertible Notes and Warrants. |

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| - Definition
The entire disclosure for earnings per share.
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