| **Equipment on Operating Leases (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 |
|--------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Scheduled minimum rental payments for operating leases**                                 |          |          |          |
| 2013                                                                                       | $ 754         |          |          |
| 2014                                                                                       | 523           |          |          |
| 2015                                                                                       | 318           |          |          |
| 2016                                                                                       | 172           |          |          |
| 2017                                                                                       | 63            |          |          |
| Thereafter                                                                                 | 19            |          |          |
| Total                                                                                      | 1,849         |          |          |
| Equipment leased to others                                                                 |          |          |          |
| **Equipment on operating leases**                                                          |          |          |          |
| Equipment on operating leases, at cost                                                     | 4,410         | 4,082         | 4,241         |
| Less: Accumulated depreciation                                                             | (1,451)       | (1,471)       | (1,530)       |
| Equipment on operating leases, net                                                         | $ 2,959       | $ 2,611       | $ 2,711       |

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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cumulative amount of depreciation, depletion and amortization (related to property, plant and equipment, but not including land) that has been recognized in the income statement.
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| - Definition
Amount of minimum lease payments to be received by the lessor for capital leases.
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Amount of minimum lease payments to be received by the lessor in the next fiscal year following the latest fiscal year for capital leases.
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| - Definition
Amount of minimum lease payments to be received by the lessor after the fifth fiscal year following the latest fiscal year for capital leases.
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Amount of minimum lease payments to be received by the lessor in the fifth fiscal year following the latest fiscal year for capital leases.
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Amount of minimum lease payments to be received by the lessor in the fourth fiscal year following the latest fiscal year for capital leases.
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Amount of minimum lease payments to be received by the lessor in the third fiscal year following the latest fiscal year for capital leases.
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| - Definition
Amount of minimum lease payments to be received by the lessor in the second fiscal year following the latest fiscal year for capital leases.
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| - Definition
Gross amount of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, net of accumulated depreciation, depletion and amortization, of long-lived physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.
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