| **Balance Sheet Details (Inventories Schedule) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2012 | Mar. 31, 2012 |
|-----------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Balance Sheet Related Disclosures [Abstract]**                                                          |          |          |  |
| Raw materials and work in process                                                                         | $ 1           | $ 0           |  |
| Finished goods                                                                                            | 58            | 59            |  |
| Inventories                                                                                               | $ 59          | $ 59          | [1] |
|                                                                                                           |
| [1]Derived from audited consolidated financial statements.                                                |

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| - Definition
Amount before last-in first-out (LIFO) and valuation reserves of merchandise or goods held by the entity that are readily available for sale.
+ References
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| - Definition
Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).
+ References
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| - Definition
The aggregate carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of items which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.
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