| **Net Income Per Share**                         | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| **Earnings Per Share Reconciliation [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Net Income Per Share                             | (15) NET INCOME 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, common stock through our ESPP, warrants, and other convertible securities using the treasury stock method. Three Months Ended June 30,(In millions, except per share amounts)2013 2012Net income$222 $201Shares used to compute net income per share:   Weighted-average common stock outstanding - basic304 317Dilutive potential common shares8 3Weighted-average common stock outstanding - diluted312 320Net income per share:   Basic$0.73 $0.63Diluted$0.71 $0.63 Potentially dilutive shares of common stock related to our 0.75% Convertible Senior Notes due 2016 issued during the fiscal year ended March 31, 2012, which have a conversion price of $31.74 per share and the associated Warrants, which have a conversion price of $41.14 per share were excluded from the computation of Diluted EPS for the three months ended June 30, 2013 and 2012 as their inclusion would have had an antidilutive effect resulting from the conversion price. The associated Convertible Note Hedge was excluded from the calculation of diluted shares as the impact is always considered antidilutive since the call option would be exercised by us when the exercise price is lower than the market price. See Note 12 for additional information related to our 0.75% Convertible Senior Notes due 2016 and related Convertible Note Hedge and Warrants. |

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| - Definition
The entire disclosure for earnings per share.
+ References
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