Segment Disclosures (Schedule Of Business Segment Reporting Information) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Segment Reporting Information [Line Items]
Revenues	$ 460,408	$ 701,699	$ 1,243,214	$ 1,330,634
Operating expenses	146,107	168,929	295,615	314,954
Cost of product sales	50,509	152,876	299,745	321,970
Other operating (income) expense	(3,913)	5,024	(3,402)	(1,917)
Earnings of non-controlled entities	(33,689)	(40,785)	(77,349)	(72,040)
Operating margin	301,394	415,655	728,605	767,667
Depreciation, amortization and impairment	58,540	62,530	122,074	124,401
G&A expense	42,168	52,383	79,076	98,378
Operating profit	200,686	300,742	527,455	544,888
Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	315,735	533,984	944,624	1,002,499
Operating expenses	103,405	132,850	209,287	235,542
Cost of product sales	45,616	148,166	278,958	310,596
Other operating (income) expense	(138)	(1,031)	(2,030)	(6,399)
Earnings of non-controlled entities	(4,592)	2,950	(18,812)	3,997
Operating margin	171,444	251,049	477,221	458,763
Depreciation, amortization and impairment	41,029	44,637	87,088	89,064
G&A expense	30,661	37,560	57,315	70,373
Operating profit	99,754	168,852	332,818	299,326
Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	146,254	169,056	301,753	330,414
Operating expenses	45,917	38,764	92,689	84,470
Cost of product sales	4,893	4,710	20,787	11,374
Other operating (income) expense	(3,775)	6,055	(1,372)	4,482
Earnings of non-controlled entities	(29,097)	(43,735)	(58,537)	(76,037)
Operating margin	128,316	163,262	248,186	306,125
Depreciation, amortization and impairment	15,877	16,549	31,788	32,558
G&A expense	11,507	14,823	21,761	28,005
Operating profit	100,932	131,890	194,637	245,562
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(1,581)	(1,341)	(3,163)	(2,279)
Operating expenses	(3,215)	(2,685)	(6,361)	(5,058)
Cost of product sales	0	0	0	0
Other operating (income) expense	0	0	0	0
Earnings of non-controlled entities	0	0	0	0
Operating margin	1,634	1,344	3,198	2,779
Depreciation, amortization and impairment	1,634	1,344	3,198	2,779
G&A expense	0	0	0	0
Operating profit	0	0	0	0
Service [Member]
Segment Reporting Information [Line Items]
Revenues	411,815	506,405	870,210	967,197
Service [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	279,759	347,630	594,078	657,201
Service [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	133,637	160,116	279,295	312,275
Service [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(1,581)	(1,341)	(3,163)	(2,279)
Product [Member]
Segment Reporting Information [Line Items]
Revenues	43,277	189,989	362,397	352,984
Product [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	34,463	184,695	347,449	341,977
Product [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	8,814	5,294	14,948	11,007
Product [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Product and Service, Other [Member]
Segment Reporting Information [Line Items]
Revenues	5,316	5,305	10,607	10,453
Product and Service, Other [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	1,513	1,659	3,097	3,321
Product and Service, Other [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	3,803	3,646	7,510	7,132
Product and Service, Other [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	$ 0	$ 0	$ 0	$ 0

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