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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Percentage of fair value of reporting unit in excess of carrying amount.

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No definition available.

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DISPOSITION AND IMPAIRMENTS Narrative 2 (Details) $ in Thousands		3 Months Ended			9 Months Ended
	Oct. 01, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Goodwill [Line Items]
Goodwill impairment losses	$ 0	$ 34,060	$ 0		$ 34,060	$ 225,000
Goodwill		$ 732,356			732,356		$ 766,416
Houston Pipeline
Goodwill [Line Items]
Number of assets		2
Pipeline Segment \| Southern section of Houston Pipeline
Goodwill [Line Items]
Property, plant and equipment, net		$ 0			0
Pipeline Segment \| Southern section of Houston Pipeline \| Asset impairment losses
Goodwill [Line Items]
Long-lived asset impairment charge		59,200
Crude Oil Pipelines [Member] \| Pipeline Segment
Goodwill [Line Items]
Goodwill impairment losses				$ 225,000
Reporting unit, percentage of fair value in excess of carrying amount	4.00%
Goodwill	$ 308,600	$ 308,600			$ 308,600