Investments in Non-Controlled Entities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Revenues	$ 628,935	$ 678,779
Operating	146,025	143,296
Trade accounts receivable	134,120		$ 104,164
Other accounts receivable	31,937		25,007
Long-term receivables	20,646		20,844
Change in Equity Method Investments [Roll Forward]
Investments at December 31, 2018	1,076,306
Additional investment	76,634
Indemnification settlement	(5,000)
Proportionate share of earnings	31,719
Amortization of excess investment and capitalized interest	(464)
Earnings of non-controlled entities	31,255	34,538
Distributions from operations of non-controlled entities	43,069	51,754
Distributions from returns of investments in non-controlled entities	7,500	0
Investments at March 31, 2019	1,128,626
Service [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	460,792	431,937
Product [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	162,995	241,592
Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Other Revenues from Transactions with Related Party	$ 1,500	500
BridgeTex [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	30.00%
BridgeTex [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Trade accounts receivable	$ 284		318
Other accounts receivable	779		1,549
Accounts Payable, Other, Current	179
BridgeTex [Member] | Equity Method Investee [Member] | Service [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	$ 10,145	9,864
Double Eagle Pipeline Llc [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
Double Eagle Pipeline Llc [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Trade accounts receivable	$ 583		546
Double Eagle Pipeline Llc [Member] | Equity Method Investee [Member] | Service [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	$ 1,659	1,544
HoustonLink Pipeline Company LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
MVP Terminalling, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
MVP Terminalling, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Other accounts receivable	$ 361		397
Powder Springs Logistics, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
Powder Springs Logistics, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Other accounts receivable	$ 269
Long-term receivables	2,725		2,221
Powder Springs Logistics, LLC [Member] | Equity Method Investee [Member] | Product [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	$ 0	2,719
Saddlehorn Pipeline Company [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	40.00%
Saddlehorn Pipeline Company [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Other accounts receivable	$ 109		183
Saddlehorn Pipeline Company [Member] | Equity Method Investee [Member] | Service [Member]
Schedule of Equity Method Investments [Line Items]
Revenues	$ 552	538
Seabrook Logistics, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
Seabrook Logistics, LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Operating	$ 6,909	$ 0
Accounts Payable, Other, Current	$ 1,646		$ 1,140
Texas Frontera Llc [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
Texas Frontera Llc [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Accounts Payable, Other, Current	$ 83