UNCONSOLIDATED AFFILIATES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	$ 36,340	$ 33,320
Unconsolidated Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Expenses from Transactions with Related Parties	14,500	15,600
Northern Border Pipeline
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	20,125	20,239
Roadrunner
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	9,141	7,749
Overland Pass Pipeline
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	5,008	2,972
Other Unconsolidated Affiliates
Schedule of Equity Method Investments [Line Items]
Equity in net earnings from investments	$ 2,066	$ 2,360

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

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