Revenue Recognition - Disaggregated Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	$ 125	$ 107
Lease revenue – related parties	14	14
Total revenue	139	121
Related Parties
Disaggregation of Revenue [Line Items]
Lease revenue – related parties	14	14
Transportation Services | Third Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	39	29
Transportation Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	44	55
Storage Services | Third Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	2
Storage Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	2
Terminaling Services | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	30	12
Terminaling Services, Major Maintenance | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	2	0
Product Revenue | Third Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	0	0
Product Revenue | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	6	7
Transportation Services, Non-lease Service | Related Parties
Disaggregation of Revenue [Line Items]
Total Topic 606 revenue	$ 1	$ 1