Fair Values (Details Textuals) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Fair Value Assets Measured On Recurring Basis Financial Statement Captions [Line Items] | |||
| Impairment Of Goodwill Prepaid Services | $ 219 | ||
| Impairment Charge - Technology And Other Assets writedown to Fair Value | 165 | ||
| Goodwill and intangible asset impairment | $ 0 | 384 | $ 0 |
| Fair Value, Measurements, Nonrecurring [Member] | |||
| Fair Value Assets Measured On Recurring Basis Financial Statement Captions [Line Items] | |||
| Assets measured at fair value for impairment | $ 0 | $ 0 | |