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GOODWILL Table - Balances of and Changes in the Carrying Amount of Goodwill by Segment (Details) - USD ($) $ in Thousands			3 Months Ended	12 Months Ended
	Dec. 07, 2020	Oct. 01, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill				$ 766,416	$ 1,005,853	$ 1,005,853
Goodwill impairment loss		$ 0		(225,000)	0	0
Goodwill, accumulated impairment loss				(225,000)
Texas City Sale	$ (14,437)
Goodwill, gross				991,416
Pipeline Segment
Goodwill [Roll Forward]
Goodwill				479,231	704,231	704,231
Goodwill, accumulated impairment loss				(225,000)
Goodwill, gross				704,231
Pipeline Segment \| Crude Oil Pipelines
Goodwill [Roll Forward]
Goodwill				308,600
Goodwill impairment loss			$ (225,000)	(225,000)
Texas City Sale	0
Storage Segment
Goodwill [Roll Forward]
Goodwill				287,185	$ 301,622	$ 301,622
Goodwill impairment loss				0
Goodwill, accumulated impairment loss				0
Texas City Sale	$ (14,437)
Goodwill, gross				$ 287,185