Goodwill and Other Intangible Assets Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Finite-Lived Intangible Assets [Line Items] | |||
| Finite-lived intangible assets acquired | $ 185 | ||
| Customer-related | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Finite-lived intangible assets acquired | $ 82 | $ 196 | |
| Weighted average useful life of finite-lived intangible assets acquired | 7 years | 7 years | |
| Marketing Expense | Retail Partner Contracts | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Amortization expense | $ 100 | $ 84 | $ 81 |
| Other Expense | Finite-Lived Intangible Assets, Excluding Retail Partner Contracts | |||
| Finite-Lived Intangible Assets [Line Items] | |||
| Amortization expense | $ 74 | $ 63 | $ 28 |