Investments in Non-Controlled Entities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Schedule of Equity Method Investments [Line Items]
Transportation and terminals revenue	$ 431,937	$ 392,671
Product sales revenue	241,592	245,620
Trade accounts receivable	105,089		$ 138,779
Other accounts receivable	24,880		14,561
Change in Equity Method Investments [Roll Forward]
Investments at December 31, 2017	1,082,511
Additional investment	60,976
Other Adjustment to Equity Investment	502
Proportionate share of earnings	35,140
Amortization of excess investment and capitalized interest	(602)
Earnings of non-controlled entities	34,538	21,446
Distributions of earnings from investments in non-controlled entities	51,754	21,605
Distributions in excess of earnings of non-controlled entities		0
Investments at March 31, 2018	1,126,773
Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Other Revenues from Transactions with Related Party	$ 500	1,000
BridgeTex [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
BridgeTex [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Transportation and terminals revenue	$ 9,900	8,900
Trade accounts receivable	800
Other accounts receivable	$ 100
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]
Transportation and terminals revenue	$ 1,500	800
Trade accounts receivable	$ 600		500
HoustonLink Pipeline Company LLC [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
HoustonLink Pipeline Company LLC [Member] | Equity Method Investee [Member]
Schedule of Equity Method Investments [Line Items]
Accounts Payable, Other, Current			100
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	$ 400		400
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]
Product sales revenue	$ 2,700	0
Other accounts receivable	$ 2,100		900
Powder Springs Logistics, LLC [Member] | Equity Method Investee [Member] | Guarantee of Indebtedness of Others [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%
Guarantor Obligations, Maximum Exposure, Undiscounted	$ 25,000
Guarantees, Fair Value Disclosure	$ 400
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]
Transportation and terminals revenue	$ 500	$ 500
Other accounts receivable	$ 200		100
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]
Other accounts receivable	$ 300		$ 200
Texas Frontera Llc [Member]
Schedule of Equity Method Investments [Line Items]
Interest in equity method investment	50.00%