v3.21.2

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 |  |

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