Segment Information - Additional Information (Detail) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
|
Feb. 01, 2018
USD ($)
|
Mar. 31, 2018
USD ($)
Segment
refinery
|
Mar. 31, 2017
USD ($)
|
|
| Segment Reporting Information [Line Items] | |||
| Number of reportable segments | Segment | 3 | ||
| Number of refineries | refinery | 6 | ||
| Income from operations | $ 440 | $ 291 | |
| Refining & Marketing | |||
| Segment Reporting Information [Line Items] | |||
| Income from operations | $ (181) | ||
| Midstream | |||
| Segment Reporting Information [Line Items] | |||
| Income from operations | $ 181 | ||