| **Balance Sheet Details (Inventories Schedule) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2014                                               | Mar. 31, 2014                                               |
|-----------------------------------------------------------------------------------------------------------|-------------------------------------------------------------|-------------------------------------------------------------|
| **Balance Sheet Related Disclosures [Abstract]**                                                          |                                                        |                                                        |  |
| Finished goods                                                                                            | $ 38us-gaap_InventoryFinishedGoods                          | $ 55us-gaap_InventoryFinishedGoods                          |  |
| Raw materials and work in process                                                                         | 1us-gaap_InventoryWorkInProcessAndRawMaterialsNetOfReserves | 1us-gaap_InventoryWorkInProcessAndRawMaterialsNetOfReserves |  |
| Inventories                                                                                               | $ 39us-gaap_InventoryNet                                    | $ 56us-gaap_InventoryNet                                    | [1] |
|                                                                                                           |
| [1]Derived from audited consolidated financial statements.                                                |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or 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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