Agreements and Transactions with Affiliates - Balances with Affiliates (Detail) - USD ($) $ in Millions	Jun. 30, 2020	Dec. 31, 2019
Related Party Transaction [Line Items]
Accounts receivable	$ 111	$ 138
Accounts payable	102	100
Related Party Transaction, Due from (to) Related Party, Noncurrent	2	0
Unconsolidated Affiliates
Related Party Transaction [Line Items]
Accounts receivable	20	21
Accounts payable	79	78
Phillips 66
Related Party Transaction [Line Items]
Accounts receivable	91	117
Accounts payable	23	20
Enbridge
Related Party Transaction [Line Items]
Accounts payable	$ 0	$ 2

Amount for accounts payable to related parties. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of receivables arising from transactions with related parties due within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Amount of receivables to be collected from related parties net of obligations owed to related parties after one year or beyond the normal operating cycle, if longer where one party can exercise control or significant influence over another party including, but not limited to, affiliates, owners or officers and their immediate families and pension trusts.

+ References

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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