Debt (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Short-term Debt [Line Items] | ||
| Outstanding Balance | $ 4,812,000 | $ 3,480,000 |
| Face amount of eligible notes issued | $ 2,000,000 | |
| Short-term Debt [Member] | ||
| Short-term Debt [Line Items] | ||
| Year-End Stated Rate on Debt | 0.79% | 0.69% |
| Fees to maintain the secured financing facility | $ 6,700 | $ 7,000 |
| Commercial Paper [Member] | ||
| Short-term Debt [Line Items] | ||
| Outstanding Balance | $ 2,120,000 | $ 769,000 |
| Commercial Paper [Member] | Short-term Debt [Member] | ||
| Short-term Debt [Line Items] | ||
| Year-End Stated Rate on Debt | 0.38% | 0.29% |
| Other Short Term Borrowings [Member] | ||
| Short-term Debt [Line Items] | ||
| Outstanding Balance | $ 2,692,000 | $ 2,711,000 |
| Other Short Term Borrowings [Member] | Bank Overdrafts [Member] | ||
| Short-term Debt [Line Items] | ||
| Outstanding Balance | $ 410,000 | $ 470,000 |
| Other Short Term Borrowings [Member] | Short-term Debt [Member] | ||
| Short-term Debt [Line Items] | ||
| Year-End Stated Rate on Debt | 1.11% | 0.81% |