UNCONSOLIDATED AFFILIATES (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	$ 801,794	$ 797,613	$ 805,032
Equity method goodwill	16,500	16,500
Equity in net earnings from investments	147,720	122,520	143,241
Impairment of equity investments	0	0	(37,730)
Natural Gas Gathering And Processing
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	27,973	27,018	22,757
Equity in net earnings from investments	4,857	3,757	(1,123)
Natural Gas Liquids [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	414,454	416,648	423,494
Equity in net earnings from investments	34,643	21,000	39,938
Unconsolidated Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Related Party Transaction, Expenses from Transactions with Related Party	$ 82,800	62,800	135,400
Northern Border Pipeline [Member]
Schedule of Equity Method Investments [Line Items]
Net ownership percentage	50.00%
Investments in unconsolidated affiliates	$ 265,096	283,170
Equity in net earnings from investments	71,106	64,470	75,409
Payments to Acquire Equity Method Investments	$ 0	0	0
Cash Distribution Percentage of Equity Method Investment	100.00%
Overland Pass Pipeline Company [Member]
Schedule of Equity Method Investments [Line Items]
Net ownership percentage	50.00%
Investments in unconsolidated affiliates	$ 401,244	403,011
Equity in net earnings from investments	$ 32,519	19,434	38,618
Cash Distribution Percentage of Equity Method Investment	100.00%
Overland Pass Pipeline Company [Member] \| Natural Gas Liquids [Member]
Schedule of Equity Method Investments [Line Items]
Net ownership percentage	50.00%
Roadrunner Gas Transmission [Member]
Schedule of Equity Method Investments [Line Items]
Net ownership percentage	50.00%
Investments in unconsolidated affiliates	$ 94,271	70,777
Equity in net earnings from investments	$ 37,114	33,293	29,017
Cash Distribution Percentage of Equity Method Investment	100.00%
Other Unconsolidated Affiliates [Member]
Schedule of Equity Method Investments [Line Items]
Investments in unconsolidated affiliates	$ 41,183	40,655
Equity in net earnings from investments	$ 6,981	$ 5,323	$ 197
Venice Energy Services Company [Member] \| Natural Gas Gathering And Processing
Schedule of Equity Method Investments [Line Items]
Net ownership percentage			10.20%
Impairment of equity investments			$ (30,500)
ImpairmentOfEquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity			$ (22,300)
Chisholm Pipeline Company [Member] \| Natural Gas Liquids [Member]
Schedule of Equity Method Investments [Line Items]
Net ownership percentage			50.00%
Impairment of equity investments			$ (7,200)

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Impairment Of Equity Method Investment, Difference Between Carrying Amount And Underlying Equity

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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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