| **Condensed Consolidated Balance Sheets (Parenthetical) (USD $)In Millions, except Per Share data, unless otherwise specified** | Jun. 30, 2013 | Mar. 31, 2013 |
|---------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Receivables, allowances                                                                                                         | $ 160         | $ 200         |
| Interest rate percentage on convertible senior notes, due 2016                                                                  | 0.75%         | 0.75%         |
| Preferred stock, par value                                                                                                      | $ 0.01        | $ 0.01        |
| Preferred stock, shares authorized                                                                                              | 10            | 10            |
| Common stock, par value                                                                                                         | $ 0.01        | $ 0.01        |
| Common stock, shares authorized                                                                                                 | 1,000         | 1,000         |
| Common stock, shares issued                                                                                                     | 306           | 301           |
| Common stock, shares outstanding                                                                                                | 306           | 301           |

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| - Definition
A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.
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| - Definition
Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.
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| - Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws.
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| - Definition
Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.
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| - Definition
Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.
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| - Definition
Interest rate stated in the contractual debt agreement.
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Face amount or stated value per share of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer); generally not indicative of the fair market value per share.
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| - Definition
The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.
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