Supplemental Cash Flow Information - Summary of Supplemental Cash Flow Information (Detail) - USD ($) $ in Millions |
9 Months Ended | |
|---|---|---|
Sep. 30, 2015 |
Sep. 30, 2014 |
|
| Net cash provided by operating activities included: | ||
| Interest paid (net of amounts capitalized) | $ 12.4 | $ 1.8 |
| Income taxes paid | 0.1 | 0.0 |
| Non-cash investing and financing activities: | ||
| Net transfers of property, plant and equipment to materials and supplies inventories | 0.0 | 0.7 |
| Property, plant and equipment contributed by MPC | $ 0.0 | $ 0.1 |