| **Balance Sheet Details (Property And Equipment, Net Schedule) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2012 | Mar. 31, 2012 |
|---------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | $ 1,275       | $ 1,219       |  |
| Less: accumulated depreciation                                                                                            | (725)         | (651)         |  |
| Property and equipment, net                                                                                               | 550           | 568           | [1] |
| Computer equipment and software                                                                                           |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 649           | 575           |  |
| Building                                                                                                                  |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 340           | 339           |  |
| Leasehold improvements                                                                                                    |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 131           | 121           |  |
| Office equipment                                                                                                          |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 72            | 72            |  |
| Land                                                                                                                      |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 64            | 64            |  |
| Machinery and equipment                                                                                                   |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | 10            | 10            |  |
| Construction in progress                                                                                                  |          |          |  |
| **Property, Plant and Equipment [Line Items]**                                                                            |          |          |  |
| Property, plant and equipment, gross                                                                                      | $ 9           | $ 38          |  |
|                                                                                                                           |
| [1]Derived from audited consolidated financial statements.                                                                |

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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
+ References
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| X                                                                                                                                                                      |
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
+ References
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