Variable Interest Entities (Details)
bbl / d in Thousands, $ in Millions |
Mar. 31, 2018
USD ($)
|
Dec. 31, 2017
USD ($)
|
Jan. 01, 2017
bbl / d
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments |
$ 4,817
|
$ 4,787
|
|
| Crowley Coastal Partners |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| VIE, maximum loss exposure, amount |
$ 487
|
|
|
| MarkWest Utica EMG |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
56.00%
|
|
|
| Equity method investments |
$ 2,100
|
|
|
| Ohio Gathering |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
34.00%
|
|
|
| Sherwood Midstream |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
50.00%
|
|
|
| Equity method investments |
$ 260
|
|
|
| Ohio Fractionation |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Capacity | bbl / d |
|
|
20
|
| Sherwood Midstream Holdings |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
81.00%
|
|
|
| Equity method investments |
$ 151
|
|
|
| Sherwood Midstream Holdings | Direct Ownership Interest |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
|
|
79.00%
|
| Sherwood Midstream Holdings | Indirect Ownership Interest |
|
|
|
| Variable Interest Entity [Line Items] |
|
|
|
| Equity method investments, ownership percentage |
|
|
10.50%
|