| **Debt (Tables)**                                            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| **Debt [Abstract]**                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Debt and Related Weighted Average Contractual Interest Rates | Note 9 – Debt                        Debt and the related weighted average contractual interest rates are summarized as follows:                     Weighted average      contractual interest rates  December 31, March 31,  December 31, March 31, (Dollars in millions)2013201320132013Commercial paper$ 27,012 $ 24,590  0.19%  0.24%Unsecured notes and loans payable  47,938   46,707  1.98%  2.19%Secured notes and loans payable  7,195   7,009  0.55%  0.60%Carrying value adjustment  548   526      Total debt$ 82,693 $ 78,832  1.27%  1.43% |

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| - Definition
Tabular disclosure of information pertaining to short-term and long-debt instruments or arrangements, including but not limited to identification of terms, features, collateral requirements and other information necessary to a fair presentation.
+ References
No definition available.
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