Other Assets and Liabilities from Related Parties (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Other current assets	$ 45	$ 110
Current Assets, Related Parties	600	656
Operating Lease, Right-of-Use Asset	352	365
Other Assets, Related Parties, Noncurrent	677	303
Operating Lease, Liability, Current	67	66
Current Liabilities, Related Parties	297	1,008
Operating Lease, Liability, Noncurrent	284	302
Liabilities, Related Parties, Noncurrent	290	290
MPC
Related Party Transaction [Line Items]
Receivables - related parties	538	621
Prepaid Insurance	15	9
Sales-type Lease, Interest Income	26	4
Sales-type Lease, Unguaranteed Residual Asset	19	7
Due from Related Parties, Noncurrent	28	21
Operating Lease, Right-of-Use Asset	231	232
Net Investment in Lease, Noncurrent	399	43
Due to Related Parties, Current	227	911
Operating Lease, Liability, Current	1	1
Operating Lease, Liability, Noncurrent	230	230
Other Affiliates [Member]
Related Party Transaction [Line Items]
Receivables - related parties	21	22
Due to Related Parties, Current	16	37
Minimum Committed Volume Contracts [Member] | MPC
Related Party Transaction [Line Items]
Deferred Revenue Related Parties	38	42
Reimbursable Projects [Member] | MPC
Related Party Transaction [Line Items]
Deferred Revenue Related Parties	14	16
Deferred Revenue, Noncurrent, Related Parties	54	53
Other Noncurrent Liabilities [Member] | Other Affiliates [Member]
Related Party Transaction [Line Items]
Deferred Revenue Related Parties	1	1
Other Noncurrent Liabilities [Member] | Other Affiliates [Member]
Related Party Transaction [Line Items]
Deferred Revenue, Noncurrent, Related Parties	$ 6	$ 7