ACQUISITIONS AND DIVESTITURES - Schedule of Acquisition Consideration (Details) - USD ($) $ / shares in Units, $ in Millions	Oct. 15, 2024	Sep. 25, 2023
EnLink Acquisition
Business Combination Segment Allocation [Line Items]
Public common units outstanding (in shares)	200,300,000
Business acquisition, share price (in dollars per share)	$ 14.90
Cash consideration	$ 2,985
Liabilities incurred	300
Total consideration	$ 3,285
Percentage of voting interests acquired	100.00%
EnLink Acquisition \| GIP
Business Combination Segment Allocation [Line Items]
Percentage of voting interests acquired	43.00%
Magellan Acquisition
Business Combination Segment Allocation [Line Items]
Public common units outstanding (in shares)		202,100,000
Business acquisition, share price (in dollars per share)		$ 25.00
Cash consideration		$ 5,052
ONEOK exchange ratio per Magellan unit (in shares)		0.667
Shares of ONEOK common stock issued (in shares)		134,800,000
ONEOK common stock closing price on Sept (USD per share)		$ 66.54
Equity consideration		$ 9,062
Total consideration		14,114
Magellan Acquisition \| Common Stock
Business Combination Segment Allocation [Line Items]
Equity consideration		8,969
Magellan Acquisition \| Replacement Equity Awards
Business Combination Segment Allocation [Line Items]
Equity consideration		$ 93

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