Debt and Capital Lease Obligations (Non-cash Financing Transactions) (Narrative) (Details) - USD ($) $ in Millions |
6 Months Ended | |
|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
|
| Debt and Capital Lease Obligations [Abstract] | ||
| Non-cash borrowings and repayments of debt | $ 2,453.1 | $ 6,546.2 |