Other, Net (Schedule of Other, Net) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
|
| Schedule Of Other, Net [Line Items] | ||||
| AFUDC Equity | $ 4.9 | $ 8.4 | ||
| Miscellaneous | 0.0 | 0.8 | ||
| Total Other, net | $ 4.9 | $ 9.2 | ||
| Predecessor [Member] | ||||
| Schedule Of Other, Net [Line Items] | ||||
| AFUDC Equity | $ 2.7 | $ 4.3 | ||
| Miscellaneous | (0.1) | 0.1 | ||
| Total Other, net | $ 2.6 | $ 4.4 | ||