| **Interest And Other Income (Expense), Net** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
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| **Interest and Other Income [Abstract]**     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Interest And Other Income (Expense), Net     | (16)  INTEREST AND OTHER INCOME (EXPENSE), NETInterest and other income (expense), net, for the fiscal years ended March 31, 2016, 2015 and 2014 consisted of (in millions):  Year Ended March 31, 2016 2015 2014Loss on conversion of Convertible Notes$(10) $— $—Interest expense(28) (31) (30)Interest income15 10 5Net gain (loss) on foreign currency transactions(14) (62) 4Net gain (loss) on foreign currency forward contracts15 59 (5)Other income, net1 1 —Interest and other income (expense), net$(21) $(23) $(26) |

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| - Definition
The entire disclosure for interest and other income.
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