Consolidated Statements of Comprehensive Income - USD ($) $ in Millions |
3 Months Ended | |
|---|---|---|
Mar. 31, 2018 |
Mar. 31, 2017 |
|
| Statement of Comprehensive Income [Abstract] | ||
| Net income | $ 235 | $ 101 |
| Defined benefit postretirement and post-employment plans: | ||
| Actuarial changes, net of tax of $3 and $3 | 7 | 4 |
| Prior service costs, net of tax of ($2) and ($4) | (7) | (7) |
| Other, net of tax of ($1) and $0 | (2) | 0 |
| Other comprehensive loss | (2) | (3) |
| Comprehensive income | 233 | 98 |
| Less comprehensive income attributable to: | ||
| Redeemable noncontrolling interest | 16 | 16 |
| Noncontrolling interests | 182 | 55 |
| Comprehensive income attributable to MPC | $ 35 | $ 27 |