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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Term of lessor's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Section S99
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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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No definition available.

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Revenue Recognition - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019 term	Jan. 01, 2019 USD ($)	Jan. 01, 2018 USD ($)
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Impact of changes in accounting policy		$ (9)	$ (2)
Transportation Services Operating Leases Five Year Terms
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Lease revenue related party agreements, term	10 years
Lessor, number of renewal terms \| term	2
Lease revenue related party agreements, renewal term	5 years
Transportation Services Operating Leases One Year Terms
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Lease revenue related party agreements, term	10 years
Lessor, number of renewal terms \| term	10
Lease revenue related party agreements, renewal term	1 year
Transportation Services Operating Leases
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Lease revenue related party agreements, term	10 years
Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect transition adjustment resulting from earlier recognition of revenue			(2)
Accounting Standards Update 2014-09 \| Difference between Revenue Guidance in Effect before and after Topic 606
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Cumulative effect transition adjustment resulting from earlier recognition of revenue			5
Mars Oil Pipeline Company LLC (“Mars”) \| Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Impact of changes in accounting policy		$ (9)	$ (7)