| **Goodwill and Other Intangible assets, Net Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions** | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Finite-Lived Intangible Assets [Line Items]**                                                                           |            |   |   |
| Amortization of Intangible Assets                                                                                         | $ 2             | $ 3 | $ 7 |
| Finite-Lived Intangible Assets, Gross                                                                                     | 144             | 150 |   |
| Finite-Lived Intangible Assets, Accumulated Amortization                                                                  | (138)           | (142) |   |
| Finite-Lived Intangible Assets, Net                                                                                       | 6               | 8 |   |
| Other Intangible Assets [Member]                                                                                          |            |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                                                           |            |   |   |
| Finite-Lived Intangible Assets, Gross                                                                                     | 83              | 84 |   |
| Finite-Lived Intangible Assets, Accumulated Amortization                                                                  | (77)            | (76) |   |
| Finite-Lived Intangible Assets, Net                                                                                       | 6               | 8 |   |
| Customer base and relationships                                                                                           |            |   |   |
| **Finite-Lived Intangible Assets [Line Items]**                                                                           |            |   |   |
| Finite-Lived Intangible Assets, Gross                                                                                     | 61              | 66 |   |
| Finite-Lived Intangible Assets, Accumulated Amortization                                                                  | (61)            | (66) |   |
| Finite-Lived Intangible Assets, Net                                                                                       | $ 0             | $ 0 |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
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| X                                                                                                                                                                               |
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