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DESCRIPTION OF THE BUSINESS AND BASIS OF PRESENTATION - Narrative (Details) $ in Millions	1 Months Ended		9 Months Ended
	Sep. 30, 2024 USD ($)	May 31, 2023 USD ($)	Sep. 30, 2024 USD ($) segment	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Related Party Transaction [Line Items]
Number of segments \| segment			2
Amount by which the carrying amounts of equity method investments exceeds share of underlying equity in the net assets	$ 340		$ 340		$ 352
Distributions from equity method investees			467	$ 405
Millennium
Related Party Transaction [Line Items]
Distributions from equity method investees	416
NEXUS
Related Party Transaction [Line Items]
Distributions from equity method investees		$ 371
Senior Notes \| Millennium Senior Unsecured Notes \| Millennium
Related Party Transaction [Line Items]
Amount of debt sold	$ 800		$ 800
Weighted-average coupon rate	5.88%		5.88%
Senior Notes \| NEXUS Senior Unsecured Notes \| NEXUS
Related Party Transaction [Line Items]
Amount of debt sold		$ 750
Weighted-average coupon rate		5.52%
Stonewall VIE
Related Party Transaction [Line Items]
VIE ownership percentage			85.00%
South Romeo VIE
Related Party Transaction [Line Items]
VIE ownership percentage			50.00%