| **Consolidated Statement of Shareholder's Equity (USD $)In Millions** | Total   | Capital stock | Additional paid-in capital | Accumulated other comprehensive income | Retained earnings |
|-----------------------------------------------------------------------|---------|---------------|----------------------------|----------------------------------------|-------------------|
| Balance at Mar. 31, 2011                                              | $ 6,856 | $ 915         | $ 1                        | $ 100                                  | $ 5,840           |
| Net income                                                            | 1,486   |          |                       |                                   | 1,486             |
| Other comprehensive income (loss), net of tax                         | 60      |          |                       | 60                                     |              |
| Stock-based compensation                                              | 1       |          | 1                          |                                   |              |
| Dividends                                                             | (741)   |          |                       |                                   | (741)             |
| Balance at Mar. 31, 2012                                              | 7,662   | 915           | 2                          | 160                                    | 6,585             |
| Net income                                                            | 1,331   |          |                       |                                   | 1,331             |
| Other comprehensive income (loss), net of tax                         | 51      |          |                       | 51                                     |              |
| Stock-based compensation                                              | 0       |          |                       |                                   |              |
| Dividends                                                             | (1,487) |          |                       |                                   | (1,487)           |
| Balance at Mar. 31, 2013                                              | 7,557   | 915           | 2                          | 211                                    | 6,429             |
| Net income                                                            | 857     |          |                       |                                   | 857               |
| Other comprehensive income (loss), net of tax                         | (11)    |          |                       | (11)                                   |              |
| Stock-based compensation                                              | 0       |          |                       |                                   |              |
| Dividends                                                             | (665)   |          |                       |                                   | (665)             |
| Balance at Mar. 31, 2014                                              | $ 7,738 | $ 915         | $ 2                        | $ 200                                  | $ 6,621           |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This element represents the amount of recognized equity-based compensation during the period, that is, the amount recognized as expense in the income statement (or as asset if compensation is capitalized). Alternate captions include the words "stock-based compensation".
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after tax and reclassification adjustments of other comprehensive income (loss).
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.
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