Equity - Cash Distributions (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
| General partner's distributions | $ 1.0 | $ 0.5 | $ 2.5 | $ 1.5 |
| General partner's incentive distribution rights | 7.8 | 1.0 | 16.5 | 1.9 |
| Total general partner's distributions | 8.8 | 1.5 | 19.0 | 3.4 |
| Limited partners' distributions | 37.7 | 26.4 | 106.0 | 76.0 |
| Total cash distributions declared | 46.5 | 27.9 | 125.0 | 79.4 |
| Limited Partners Common Units [Member] | ||||
| Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
| Limited partners' distributions | 37.7 | 13.2 | 74.6 | 38.0 |
| Subordinated Units [Member] | ||||
| Incentive Distribution Made to Managing Member or General Partner [Line Items] | ||||
| Limited partners' distributions | $ 0.0 | $ 13.2 | $ 31.4 | $ 38.0 |