CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
REVENUES:
Total revenues	$ 1,630,415,000	$ 1,660,834,000	$ 1,721,323,000
COSTS AND EXPENSES:
General and administrative	86,339,000	58,329,000	64,552,000
Depreciation and amortization	232,072,000	206,686,000	199,116,000
Impairment expense	0	43,003,000	0
Total costs and expenses	1,372,225,000	1,490,878,000	1,516,196,000
OPERATING INCOME	258,190,000	169,956,000	205,127,000
Equity in earnings of equity investees	47,629,000	58,291,000	66,198,000
Other expense	(9,779,000)	(15,367,000)	(4,627,000)
Income tax expense	(806,000)	(1,770,000)	(456,000)
NET INCOME (LOSS) FROM CONTINUING OPERATIONS	(393,240,000)	(33,007,000)	146,347,000
DISCONTINUED OPERATIONS (Note 4):	(47,163,000)	(30,940,000)	(28,627,000)
Loss from disposal of discontinued operations	(440,403,000)	(63,947,000)	117,720,000
NET INCOME (LOSS) FROM DISCONTINUED OPERATIONS, NET OF TAX	(73,006,000)	(87,576,000)	(90,725,000)
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON UNITHOLDERS-BASIC	$ (513,409,000)	$ (151,523,000)	$ 26,995,000
Basic Net income (Loss) per Common Unit (in dollars per unit)	$ (4.19)	$ (1.24)	$ 0.22
Diluted Net Income (Loss) per Common Unit (in dollars per unit)	$ (4.19)	$ (1.24)	$ 0.22
Basic Weighted Average Outstanding Common Units (in units)	122,464,000	122,464,000	122,535,000
Dilutive Weighted Average Outstanding Common Units (in units)	122,464,000	122,464,000	122,535,000
Interest expense, net	$ (264,729,000)	$ (261,875,000)	$ (219,065,000)
Income (loss) from continuing operations before income taxes	31,311,000	(48,995,000)	47,633,000
Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	30,505,000	(50,765,000)	47,177,000
Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, Net of Tax	8,448,000	17,758,000	99,170,000
Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax	(432,193,000)	0	0
Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ (423,745,000)	$ 17,758,000	$ 99,170,000
Income (Loss) from Continuing Operations, Per Diluted Share	$ (0.73)	$ (1.38)	$ (0.59)
Income (Loss) from Continuing Operations, Per Basic Share	$ (0.73)	$ (1.38)	$ (0.59)
Ending balance	$ 155,561,000	$ 702,194,000	$ 897,188,000
Offshore pipeline transportation
COSTS AND EXPENSES:
Cost of products and services sold	145,005,000	117,207,000	96,025,000
Marine transportation
COSTS AND EXPENSES:
Cost of products and services sold	204,830,000	196,602,000	218,403,000
Onshore transportation and services product costs
COSTS AND EXPENSES:
Cost of products and services sold	451,962,000	599,925,000	637,179,000
Onshore Transportation and Services
COSTS AND EXPENSES:
Cost of products and services sold	252,017,000	269,126,000	300,921,000
Offshore Pipeline Transportation
REVENUES:
Total revenues	531,898,000	404,919,000	382,154,000
Offshore Pipeline Transportation | Offshore pipeline transportation
REVENUES:
Total revenues	531,898,000	404,919,000	382,154,000
Marine Transportation
REVENUES:
Total revenues	319,498,000	321,616,000	327,464,000
Marine Transportation | Marine transportation
REVENUES:
Total revenues	319,498,000	321,616,000	327,464,000
Onshore Transportation and Services
REVENUES:
Total revenues	779,019,000	934,299,000	1,011,705,000
Onshore Transportation and Services Segment
REVENUES:
Total revenues	779,019,000	934,299,000	1,011,705,000
Onshore Transportation and Services Segment | Onshore transportation and services
REVENUES:
Total revenues	$ 779,019,000	$ 934,299,000	$ 1,011,705,000