Earnings per Common Share - Calculation of Basic and Dilute Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income (Numerator)
Net income	$ 1,158	$ 201	$ 681
Less: dividends attributable to participating securities	(2)	0	0
Less: Cimarex redeemable preferred stock dividends	(1)	0	0
Net income available to common stockholders	$ 1,155	$ 201	$ 681
Shares (Denominator)
Weighted-average shares - basic (in shares)	503,000,000	399,000,000	416,000,000
Dilution effect of stock awards at end of period (in shares)	1,000,000	2,000,000	2,000,000
Weighted-average shares - diluted (in shares)	504,000,000	401,000,000	418,000,000
Earnings per share:
Basic (in dollars per share)	$ 2.30	$ 0.50	$ 1.64
Diluted (in dollars per share)	$ 2.29	$ 0.50	$ 1.63