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Long-Term Debt (Details) - USD ($) $ in Millions						1 Months Ended	3 Months Ended		6 Months Ended
Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 01, 2026	May 11, 2026	Mar. 09, 2026	Mar. 04, 2026	Jan. 30, 2026	Aug. 05, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Mar. 18, 2026	Dec. 31, 2025
Long-Term Debt [Line Items]
Debt Instrument, Covenant Compliance									We were in compliance with all financial and non-financial covenants as of June 30, 2026, and through the filing of this report.
Capitalized interest costs							$ 13	$ 9	$ 28	$ 18
Civitas Resources Merger
Long-Term Debt [Line Items]
Senior Notes Assumed - Principal					$ 4,900
Assumed Credit Facility Debt Paid					$ 201
6.625% Senior Unsecured Notes Due 2034
Long-Term Debt [Line Items]
Debt Related Commitment Fees and Debt Issuance Costs			$ 16
Senior Unsecured Notes, Principal amount			$ 1,000				1,000		1,000			$ 0
8.375% Senior Unsecured Notes Due 2028
Long-Term Debt [Line Items]
Tender Offer to Repurchase Senior Notes				$ 750							$ 1,000
Debt Instrument, Repurchase Amount							922		922
Senior Notes, repurchased principal amount							894		894
Debt Instrument, Redemption Price, Percentage				103.175%
Senior Unsecured Notes, Principal amount				$ 1,350			456		456			0
8.375% Senior Unsecured Notes Due 2028 \| Premium Paid to Repurchase Senior Notes
Long-Term Debt [Line Items]
Loss on extinguishment of debt									(3)
5.000% Senior Unsecured Notes Due 2026
Long-Term Debt [Line Items]
Senior Notes, repurchased principal amount		$ 400
Debt Instrument, Redemption Price, Percentage		100.00%
6.75% Senior Unsecured Notes due 2026
Long-Term Debt [Line Items]
Senior Notes, repurchased principal amount	$ 419
Debt Instrument, Redemption Price, Percentage	100.00%
Senior Unsecured Notes, Principal amount							$ 0		$ 0			$ 419
Subsequent Event
Long-Term Debt [Line Items]
Debt Instrument, Covenant Compliance						We were in compliance with all financial and non-financial covenants as of June 30, 2026, and through the filing of this report.