Segment Reporting - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Energy Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,883	$ 1,005	$ 5,129	$ 2,811
Automotive Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	591	660	1,826	1,882
Petroleum products | Energy Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,738	926	4,785	2,551
Nitrogen fertilizer products | Energy Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	145	79	344	260
Automotive services | Automotive Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	355	327	1,024	913
Aftermarket parts sales | Automotive Segment
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 236	$ 333	$ 802	$ 969