| **Subsequent Event (Details) - Volkswagen Truck and Bus GmbH [Member] - Subsequent Event [Member] $ / shares in Units, shares in Millions, $ in Millions** | Sep. 05, 2016 USD ($) $ / shares shares |
|------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------------------------------|
| **Subsequent Event [Line Items]**                                                                                                                          |                                    |
| Percentage of equity sold to Acquirer                                                                                                                      | 19.90%                                  |
| Pro forma percentage of equity sold to Acquirer                                                                                                            | 16.60%                                  |
| Share price (in usd per share) | $ / shares                                                                                                                | $ 15.76                                 |
| Shares sold (in shares) | shares                                                                                                                           | 16.2                                    |
| Value of sale | $                                                                                                                                          | $ 256                                   |
| Maximum [Member]                                                                                                                                           |                                    |
| **Subsequent Event [Line Items]**                                                                                                                          |                                    |
| Percentage of equity sold to Acquirer                                                                                                                      | 20.00%                                  |

| X                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Stock Purchase Agreement, Ownership Percentage Transferred to Acquirer
+ References
No definition available.
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Stock Purchase Agreement, Ownership Percentage Transferred to Acquirer, Pro Forma
+ References
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| X                                                                                                                                                                                                                                                                     |
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| - Definition
Price of a single share of a number of saleable stocks of a company.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of new stock issued during the period.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.
+ References
No definition available.
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| X                                                                                                                                                        |
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