| **Balance Sheet Details (Tables)**               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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| **Balance Sheet Related Disclosures [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| Inventories Schedule                             | Inventories as of December 31, 2014 and March 31, 2014 consisted of (in millions): As of December 31, 2014As of March 31, 2014Finished goods$38$55Raw materials and work in process11Inventories$39$56                                                                                                                                                                                                                                                                                                               |
| Property And Equipment, Net Schedule             | Property and equipment, net, as of December 31, 2014 and March 31, 2014 consisted of (in millions):  As of December 31, 2014 As of March 31, 2014Computer, equipment and software$699 $718Buildings321 327Leasehold improvements127 129Office equipment, furniture and fixtures64 67Land62 63Warehouse, equipment and other9 10Construction in progress7 5 1,289 1,319Less: accumulated depreciation(828) (809)Property and equipment, net$461 $510 |
| Accrued And Other Current Liabilities Schedule   | Accrued and other current liabilities as of December 31, 2014 and March 31, 2014 consisted of (in millions):  As of December 31, 2014 As of March 31, 2014Other accrued expenses$304 $328Accrued compensation and benefits226 259Accrued royalties162 73Deferred net revenue (other)121 121Accrued and other current liabilities$813 $781                                                                                                                                         |

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| - Definition
Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.13) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 13 -Subparagraph b -Article 5
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| - Definition
Tabular disclosure of the (a) carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business (accounts payable); (b) other payables; and (c) accrued liabilities. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). An alternative caption includes accrued expenses.
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No definition available.
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| - Definition
Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6361739&loc=d3e7789-107766Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 2 -Paragraph 6 -Subparagraph a,b,c -Article 5
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