Recent Accounting Pronouncements (Recently Adopted Accounting Standards) (Lease Accounting) (Details) - USD ($) $ in Millions |
Jun. 30, 2019 |
Jan. 01, 2019 |
Dec. 31, 2018 |
|---|---|---|---|
| Accounting Policies [Abstract] | |||
| Lease right-of-use asset, net | $ 12,522.8 | $ 12,500.0 | $ 0.0 |
| Operating Lease, Liability | $ 12,638.8 | $ 12,500.0 |