v3.10.0.1

Investments in Non-Controlled Entities (Equity Method Investments) (Details) $ in Thousands, bbl in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) bbl	Dec. 31, 2016 USD ($)
Schedule of Equity Method Investments [Line Items]
Contribution of property, plant and equipment to a non-controlled entity		$ 0	$ 97,638	$ 0
Proceeds from Sale of Productive Assets		576,568	44,392	7,552
Gain (Loss) on Disposition of Other Assets		353,797	18,505	28,144
Revenues		2,826,573	2,507,661	2,205,410
Operating expenses		649,436	577,978	528,672
Cost of product sales		704,313	635,617	493,338
Accounts Receivable, Net, Current		104,164	138,779
Other accounts receivable		25,007	14,561
Change in Equity Method Investments [Roll Forward]
Investments at December 31, 2017	$ 1,082,511	1,082,511	931,255
Additional Investments		216,424
Equity Method Investment, Amount Sold		(205,776)
Other Adjustment to Equity Investment		502
Proportionate Share of Equity Earnings		183,317
Amortization of Excess Investment and Capitalized Interest		(2,200)
Income (Loss) from Equity Method Investments		181,117	120,994	78,696
Distributions from operations of non-controlled entities		196,686	146,211	87,987
Distributions from returns of investments in non-controlled entities		1,786	55,931	0
Investments at December 31, 2018		1,076,306	1,082,511	931,255
Equity Method Investment, Summarized Financial Information, Current Assets		258,698	229,342
Equity Method Investment, Summarized Financial Information, Noncurrent Assets		2,461,456	2,057,892
Equity Method Investment, Summarized Financial Information, Assets		2,720,154	2,287,234
Equity Method Investment, Summarized Financial Information, Current Liabilities		170,558	122,198
Equity Method Investment, Summarized Financial Information, Noncurrent Liabilities		73,700	74,533
Equity Method Investment, Summarized Financial Information, Liabilities		244,258	196,731
Equity Method Investment Summarized Financial Information, Equity		2,475,896	2,090,503
Equity Method Investment, Summarized Financial Information, Revenue		631,420	419,214	279,180
Equity Method Investment, Summarized Financial Information, Net Income (Loss)		416,128	256,423	164,684
Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Other Revenues from Transactions with Related Party		$ 3,900	3,600	4,200
BridgeTex [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	30.00%	30.00%
Equity Method Investment Sold Percentage	20.00%
Proceeds from Sale of Productive Assets	$ 575,600
Gain (Loss) on Disposition of Other Assets	$ 353,800
BridgeTex [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Cost of product sales			14,500
Accounts Receivable, Net, Current		$ 300
Other accounts receivable		$ 1,500
Related Party Transaction, Purchases from Related Party			6,700
Double Eagle Pipeline Llc [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Double Eagle Pipeline Llc [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Accounts Receivable, Net, Current		$ 500	500
HoustonLink Pipeline Company LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
HoustonLink Pipeline Company LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Accounts Payable, Other			$ 100
MVP Terminalling, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%	50.00%
Joint Venture, Ownership Interest			50.00%
Contribution of property, plant and equipment to a non-controlled entity			$ 97,600
Change in Equity Method Investments [Roll Forward]
Distributions from returns of investments in non-controlled entities			48,800
MVP Terminalling, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Operating expenses		$ (2,200)
Other accounts receivable		$ 400	400
Powder Springs Logistics, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Powder Springs Logistics, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Cost of product sales		$ 400
Other accounts receivable			900
Accounts Receivable, Net, Noncurrent		$ 2,200
Saddlehorn Pipeline Company [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		40.00%
Saddlehorn Pipeline Company [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Other accounts receivable		$ 200	$ 100
Seabrook Logistics, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Seabrook Logistics, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Storage Capacity | bbl			1.7
Operating expenses		$ 10,600
Other accounts receivable			$ 200
Accounts Payable, Other		$ 1,100
Texas Frontera Llc [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		50.00%
Service [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		$ 1,878,988	1,731,775	1,591,119
Service [Member] | BridgeTex [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		39,600	36,100	35,500
Service [Member] | Double Eagle Pipeline Llc [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		5,200	4,700	3,300
Service [Member] | Saddlehorn Pipeline Company [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		2,200	2,100	700
Product [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		927,220	$ 758,206	$ 599,602
Product [Member] | Powder Springs Logistics, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Revenues		$ 4,900

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