| **Operating Leases, Commitments and Contingencies, and Guarantees (Future Minimum Lease Payments and Sublease Receipts) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2014                                                      |
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| **Operating Leases, Commitments and Contingencies, and Guarantees [Abstract]**                                                                                                     |                                                               |
| Operating Leases, Future Minimum Payments Due, Next Twelve Months                                                                                                                  | $ 36us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent         |
| Operating Leases, Future Minimum Payments, Due in Two Years                                                                                                                        | 35us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears        |
| Operating Leases, Future Minimum Payments, Due in Three Years                                                                                                                      | 30us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears      |
| Operating Leases, Future Minimum Payments, Due in Four Years                                                                                                                       | 25us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears       |
| Operating Leases, Future Minimum Payments, Due in Five Years                                                                                                                       | 21us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears       |
| Operating Leases, Future Minimum Payments, Due Thereafter                                                                                                                          | 98us-gaap_OperatingLeasesFutureMinimumPaymentsDueThereafter        |
| Operating Leases, Future Minimum Payments Due                                                                                                                                      | 245us-gaap_OperatingLeasesFutureMinimumPaymentsDue                 |
| Operating Leases, Future Minimum Payments Receivable, in Five Years                                                                                                                | 1us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears |
| Operating Leases, Future Minimum Payments Receivable, Thereafter                                                                                                                   | 1us-gaap_OperatingLeasesFutureMinimumPaymentsReceivableThereafter  |
| Operating Leases, Future Minimum Payments Receivable                                                                                                                               | $ 2us-gaap_OperatingLeasesFutureMinimumPaymentsReceivable          |

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| - Definition
Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.
+ References
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| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Future minimum rental payments in aggregate as of the balance sheet date under operating leases.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.
+ References
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