Operating Segments, Results (Details) - USD ($) $ in Millions		3 Months Ended															12 Months Ended
		Dec. 31, 2018	Sep. 30, 2018	[1]	Jun. 30, 2018	[1]	Mar. 31, 2018	[1]	Dec. 31, 2017		Sep. 30, 2017	[1]	Jun. 30, 2017	[1]	Mar. 31, 2017	[1]	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Segment Reporting Information
Revenues		$ 623	$ 642		$ 569		$ 546		$ 1,114	[1]	$ 1,094		$ 614		$ 427		$ 2,380	[2]	$ 3,249	[2]	$ 1,669	[2]
Operating Income		224	215		180		177		179	[1]	147		146		131		796	[2]	603	[2]	448	[2]
Segment Reporting Operating Income Loss	[3]																835		657		475
Unallocated general and administrative expenses	[3]																(39)		(54)		(27)
Interest and financing costs, net	[2]																(233)		(330)		(195)
Equity in earnings of equity method investments	[2]																31		22		13
Other Income, net	[2]																6		11		11
Net Earnings		171	$ 166		$ 132		$ 131		53	[1]	$ 90		$ 90		$ 73		600	[2],[3],[4]	306	[2],[3],[4]	277	[2],[3],[4],[5]
Depreciation and amortization expenses	[5]																368		313		233	[3]
Additions to Other Assets, Amount	[3]																751		363		312
Total Assets		10,295							9,505	[6],[7]							10,295		9,505	[6],[7]
Operating Segments [Member] | Terminalling and Transportation Segment [Member]
Segment Reporting Information
Revenues																	1,054		838		605
Operating Income	[3]																498		397		240
Depreciation and amortization expenses	[3]																144		117		95
Additions to Other Assets, Amount	[3]																205		188		193
Total Assets		3,458							3,045	[7]							3,458		3,045	[7]
Operating Segments [Member] | Gathering and Processing [Member]
Segment Reporting Information
Revenues																	1,263		1,129		1,064
Operating Income	[3]																310		245		235
Depreciation and amortization expenses	[3]																213		191		138
Additions to Other Assets, Amount	[3]																545		175		119
Total Assets		6,488							6,006	[7]							6,488		6,006	[7]
Operating Segments [Member] | Wholesale Segment [Member]
Segment Reporting Information
Revenues																	79		1,282		0
Operating Income																	27		15		0
Depreciation and amortization expenses																	11		5		0
Additions to Other Assets, Amount																	1		0		0
Total Assets		255							342								255		342
Intersegment Eliminations [Member]
Segment Reporting Information
Revenues																	(16)		0		0
Corporate, Non-Segment [Member]
Segment Reporting Information
Total Assets		$ 94							$ 112								94		112
Terminalling revenues [Member] | Operating Segments [Member] | Terminalling and Transportation Segment [Member]
Segment Reporting Information
Revenues	[3]																888		690		480
Pipeline transportation revenues [Member] | Operating Segments [Member] | Terminalling and Transportation Segment [Member]
Segment Reporting Information
Revenues																	160		130		125
Other Terminalling and Transportation Revenue [Member] | Operating Segments [Member] | Terminalling and Transportation Segment [Member]
Segment Reporting Information
Revenues																	6		18		0
Sales of natural gas, NGLS and condensate [Member] | Operating Segments [Member] | Gathering and Processing [Member]
Segment Reporting Information
Revenues																	436		369		103
Gas gathering and processing [Member] | Operating Segments [Member] | Gathering and Processing [Member]
Segment Reporting Information
Revenues																	330		333		264
Crude oil and water gathering [Member] | Operating Segments [Member] | Gathering and Processing [Member]
Segment Reporting Information
Revenues	[3]																336		262		582
Pass-thru and other revenue [Member] | Operating Segments [Member] | Gathering and Processing [Member]
Segment Reporting Information
Revenues																	161		165		115
Fuel Sales [Member] | Operating Segments [Member] | Wholesale Segment [Member]
Segment Reporting Information
Revenues	[8]																46		1,267		0
Other Non-fuel [Member] | Operating Segments [Member] | Wholesale Segment [Member]
Segment Reporting Information
Revenues																	$ 33		$ 15		$ 0

[1] Adjusted to include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[2] All periods include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[3] Adjusted to include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[4] Adjusted to include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[5] All periods include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[6] Adjusted to include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[7] Adjusted to include the historical results of the Predecessors. See Notes 1 and 2 for further discussion.

[8] The presentation of wholesale fuel sales was impacted by adoption of ASC 606 on January 1, 2018. Beginning January 1, 2018, the revenues and costs associated with our fuel purchase and supply arrangements were netted.