| **Accumulated Other Comprehensive Income**                               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| **Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| Comprehensive Income (Loss)                                              | (5) ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS)The changes in accumulated other comprehensive income (loss) by component, net of tax, for the three months ended December 31, 2014 and 2013 are as follows (in millions): Unrealized Gains (Losses) on Available-for-Sale Securities Unrealized Gains (Losses) on Derivative Instruments Foreign Currency Translation Adjustments TotalBalances as of September 30, 2014$(4) $7 $50 $53Other comprehensive income (loss) before reclassifications(1) 1 (30) (30)Amounts reclassified from accumulated other comprehensive income(1) 1 — —Net current-period other comprehensive income (loss)(2) 2 (30) (30)Balance as of December 31, 2014$(6) $9 $20 $23 Unrealized Gains (Losses) on Available-for-Sale Securities Unrealized Gains (Losses) on Derivative Instruments Foreign Currency Translation Adjustments TotalBalances as of September 30, 2013$(4) $(9) $75 $62Other comprehensive loss before reclassifications— (4) (9) (13)Amounts reclassified from accumulated other comprehensive income— 3 — 3Net current-period other comprehensive loss— (1) (9) (10)Balance as of December 31, 2013$(4) $(10) $66 $52The changes in accumulated other comprehensive income (loss) by component, net of tax, for the nine months ended December 31, 2014 and 2013 are as follows (in millions): Unrealized Gains (Losses) on Available-for-Sale Securities Unrealized Gains (Losses) on Derivative Instruments Foreign Currency Translation Adjustments TotalBalances as of March 31, 2014$(4) $(10) $51 $37Other comprehensive income (loss) before reclassifications(1) 11 (31) (21)Amounts reclassified from accumulated other comprehensive income(1) 8 — 7Net current-period other comprehensive income (loss)(2) 19 (31) (14)Balances as of December 31, 2014$(6) $9 $20 $23 Unrealized Gains (Losses) on Available-for-Sale Securities Unrealized Gains (Losses) on Derivative Instruments Foreign Currency Translation Adjustments TotalBalances as of March 31, 2013$(4) $— $73 $69Other comprehensive loss before reclassifications— (15) (7) (22)Amounts reclassified from accumulated other comprehensive income— 5 — 5Net current-period other comprehensive loss— (10) (7) (17)Balances as of December 31, 2013$(4) $(10) $66 $52The effects on net income of amounts reclassified from accumulated other comprehensive income (loss) for the three and nine months ended December 31, 2014 were as follows (in millions): Amount Reclassified From Accumulated Other Comprehensive Income (loss)Statement of Operations ClassificationThree Months Ended December 31, 2014Nine Months EndedDecember 30, 2014Gains and losses on available-for-sale securitiesInterest and other income (expense), net (1) (1)Net of tax$(1)$(1)Gains and losses on cash flow hedges from forward contracts    Net revenue$(2)$3Research and development35Net of tax$1$8     Total amount reclassified, net of tax $— $7The effects on net income of amounts reclassified from accumulated other comprehensive income (loss) for the three and nine months ended December 31, 2013 were as follows (in millions):  Amount Reclassified From Accumulated Other Comprehensive Income (loss)Statement of Operations Classification Three Months Ended December 31, 2013 Nine Months EndedDecember 30, 2013Gains and losses on cash flow hedges from forward contracts    Net revenue 2 4Research and development 1 1Total amount reclassified, net of tax $3 $5 |

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| - Definition
Tabular disclosure of condensed statement of comprehensive income (loss) including, but not limited to, statements of comprehensive income (loss) of consolidated entities and consolidation eliminations.
+ References
No definition available.
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