Segment Disclosures (Schedule Of Business Segment Reporting Information) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Segment Reporting Information [Line Items]
Revenues	$ 656,596	$ 638,020	$ 1,987,230	$ 1,960,890
Operating expenses	169,387	172,115	484,341	475,256
Cost of product sales	108,757	120,510	430,727	473,781
Other operating income (expense)	379	0	(1,538)	0
(Earnings) losses of non-controlled entities	(50,189)	(53,795)	(122,229)	(130,843)
Operating margin	428,262	399,190	1,195,929	1,142,696
Depreciation, amortization and impairment	56,627	56,228	181,028	161,726
G&A expense	51,156	47,389	149,534	147,235
Operating profit	320,479	295,573	865,367	833,735
Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	445,669	430,311	1,358,138	1,366,126
Operating expenses	111,839	112,279	317,328	319,670
Cost of product sales	98,144	106,756	404,814	434,632
Other operating income (expense)	(1,046)		(2,398)
(Earnings) losses of non-controlled entities	(3,373)	(3,393)	2,275	(5,614)
Operating margin	240,105	214,669	636,119	617,438
Depreciation, amortization and impairment	31,752	30,440	102,024	89,855
G&A expense	30,650	28,751	89,385	90,825
Operating profit	177,703	155,478	444,710	436,758
Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	162,861	161,247	484,178	453,044
Operating expenses	42,529	45,195	123,569	109,963
Cost of product sales	8,341	11,590	19,715	32,401
Other operating income (expense)	3,629		8,112
(Earnings) losses of non-controlled entities	(46,047)	(49,420)	(122,084)	(122,879)
Operating margin	154,409	153,882	454,866	433,559
Depreciation, amortization and impairment	14,810	15,145	45,812	40,648
G&A expense	13,666	12,766	40,378	38,127
Operating profit	125,933	125,971	368,676	354,784
Operating Segments [Member] \| Marine Storage Segment [Member]
Segment Reporting Information [Line Items]
Revenues	49,622	47,385	148,749	144,473
Operating expenses	17,921	17,178	51,404	52,835
Cost of product sales	2,272	2,164	6,198	6,748
Other operating income (expense)	(2,204)		(7,252)
(Earnings) losses of non-controlled entities	(769)	(982)	(2,420)	(2,350)
Operating margin	32,402	29,025	100,819	87,240
Depreciation, amortization and impairment	8,719	9,029	29,067	26,764
G&A expense	6,840	5,872	19,771	18,283
Operating profit	16,843	14,124	51,981	42,193
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(1,556)	(923)	(3,835)	(2,753)
Operating expenses	(2,902)	(2,537)	(7,960)	(7,212)
Cost of product sales	0	0	0	0
Other operating income (expense)	0		0
(Earnings) losses of non-controlled entities	0	0	0	0
Operating margin	1,346	1,614	4,125	4,459
Depreciation, amortization and impairment	1,346	1,614	4,125	4,459
G&A expense	0	0	0	0
Operating profit	0	0	0	0
Service [Member]
Segment Reporting Information [Line Items]
Revenues	506,432	488,775	1,473,629	1,392,960
Service [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	310,482	300,034	883,702	851,492
Service [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	150,926	145,118	454,103	409,329
Service [Member] \| Operating Segments [Member] \| Marine Storage Segment [Member]
Segment Reporting Information [Line Items]
Revenues	46,580	44,546	139,659	134,892
Service [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	(1,556)	(923)	(3,835)	(2,753)
Product [Member]
Segment Reporting Information [Line Items]
Revenues	144,807	144,403	497,791	552,792
Product [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	134,755	129,926	473,122	513,634
Product [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	8,343	12,666	19,351	32,387
Product [Member] \| Operating Segments [Member] \| Marine Storage Segment [Member]
Segment Reporting Information [Line Items]
Revenues	1,709	1,811	5,318	6,771
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	5,357	4,842	15,810	15,138
Product and Service, Other [Member] \| Operating Segments [Member] \| Refined Products Segment [Member]
Segment Reporting Information [Line Items]
Revenues	432	351	1,314	1,000
Product and Service, Other [Member] \| Operating Segments [Member] \| Crude Oil Pipeline and Terminals Segment [Member]
Segment Reporting Information [Line Items]
Revenues	3,592	3,463	10,724	11,328
Product and Service, Other [Member] \| Operating Segments [Member] \| Marine Storage Segment [Member]
Segment Reporting Information [Line Items]
Revenues	1,333	1,028	3,772	2,810
Product and Service, Other [Member] \| Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Revenues	$ 0	$ 0	$ 0	$ 0

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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