Segments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Earnings from equity method investments	$ 14,528	$ 17,367	$ 41,493	$ 52,211
Revenues	633,996	545,922	1,891,399	1,475,111
Depreciation and amortization	53,598	50,135	155,889	100,336
Income tax expense (benefit)	(2,697)	(37,249)	16,773	(33,529)
EBITDA Adjustment to Equity Earnings	4,926	6,678	14,695	20,079
Net unrealized loss (gain) related to commodity derivative instruments	4,860	(1,833)	(1,775)	(932)
General and Administrative Expense	21,904	38,389	71,267	86,920
Loss (gain) on disposal or impairment, net	(383)	41,625	(2,125)	43,801
Interest Expense	35,318	32,711	113,683	60,055
Loss on early extinguishment of debt	0	0	0	19,930
Foreign currency transaction loss (gain)	(983)	(747)	4,625	(1,758)
Other expense (income), net	(400)	(3,390)	(1,883)	(4,116)
Net loss	8,461	(19,103)	(27,300)	(19,769)
Total assets	5,297,775		5,297,775		$ 5,376,817
Equity method investments	277,021		277,021		285,281
Crude Transportation [Member]
Segment Reporting Information [Line Items]
Earnings from equity method investments	14,546	17,372	41,489	52,207
Revenues	27,309	18,824	82,025	46,822
SemCAMS [Member]
Segment Reporting Information [Line Items]
Revenues	41,939	39,500	156,715	136,412
SemGas [Member]
Segment Reporting Information [Line Items]
Revenues	71,772	54,095	183,177	167,605
Crude Facilities [Member]
Segment Reporting Information [Line Items]
Revenues	8,657	9,053	27,762	28,513
Crude Supply and Logistics [Member]
Segment Reporting Information [Line Items]
Revenues	434,591	339,874	1,259,709	928,664
HFOTCO LLC [Member]
Segment Reporting Information [Line Items]
Revenues	49,728	34,675	139,869	34,675
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Earnings from equity method investments	(18)	(5)	4	4
Revenues	0	49,902	42,142	132,421
Depreciation and amortization	747	3,663	2,263	10,377
Income tax expense (benefit)	(5,743)	(38,685)	7,231	(38,656)
Segment profit	(913)	8,421	9,878	25,084
Total assets	98,147		98,147		271,806
Equity method investments	18,923		18,923		18,919
Operating Segments [Member]
Segment Reporting Information [Line Items]
Segment profit	114,884	110,882	347,399	272,881
Operating Segments [Member] | Crude Transportation [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	12,802	11,170	38,331	23,595
Segment profit	38,135	34,585	110,310	91,864
Total assets	1,019,010		1,019,010		1,039,399
Equity method investments	258,098		258,098		266,362
Operating Segments [Member] | SemCAMS [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	5,250	4,727	15,752	13,657
Income tax expense (benefit)	2,837	1,270	8,943	4,961
Segment profit	20,543	16,704	64,104	52,606
Total assets	672,471		672,471		518,900
Operating Segments [Member] | SemGas [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	10,837	9,114	32,107	27,140
Segment profit	19,754	15,555	49,468	53,266
Total assets	725,520		725,520		714,777
Operating Segments [Member] | Crude Facilities [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	2,170	2,058	6,455	6,024
Segment profit	8,209	8,806	27,233	27,851
Total assets	148,332		148,332		153,953
Operating Segments [Member] | Crude Supply and Logistics [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	217	103	608	243
Segment profit	(7,005)	(1,693)	(15,547)	(6,294)
Total assets	600,455		600,455		674,684
Operating Segments [Member] | HFOTCO LLC [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	21,575	19,300	60,373	19,300
Income tax expense (benefit)	209	166	599	166
Segment profit	36,161	28,504	101,953	28,504
Total assets	2,033,840		2,033,840		$ 2,003,298
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(15,164)	(13,708)	(42,905)	(38,700)
Intersegment Eliminations [Member] | Crude Transportation [Member]
Segment Reporting Information [Line Items]
Revenues	7,630	8,988	22,669	22,443
Intersegment Eliminations [Member] | SemGas [Member]
Segment Reporting Information [Line Items]
Revenues	4,703	2,152	11,567	8,693
Intersegment Eliminations [Member] | Crude Facilities [Member]
Segment Reporting Information [Line Items]
Revenues	$ 2,831	$ 2,567	$ 8,669	$ 7,563