Subsequent Events (Details) $ / shares in Units, shares in Thousands, a in Thousands		1 Months Ended		3 Months Ended						9 Months Ended
	Nov. 05, 2021 USD ($) $ / shares	Dec. 31, 2021 USD ($)	Oct. 31, 2021 USD ($) shares	Sep. 30, 2021 $ / shares	Jun. 30, 2021 $ / shares	Mar. 31, 2021 $ / shares	Sep. 30, 2020 $ / shares	Jun. 30, 2020 $ / shares	Mar. 31, 2020 $ / shares	Sep. 30, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($) $ / shares	Oct. 01, 2021 USD ($) a
Subsequent Event [Line Items]
Dividends declared (usd per share) | $ / shares				$ 2.07	$ 0.56	$ 0.56	$ 0.55	$ 0.55	$ 0.55	$ 3.19	$ 1.65
Cash proceeds										$ 59,000,000	$ 58,000,000
Minimum | Forecast
Subsequent Event [Line Items]
Gain (loss) on divestiture, tax purposes		$ 1,100,000,000
Maximum | Forecast
Subsequent Event [Line Items]
Gain (loss) on divestiture, tax purposes		1,300,000,000
Sold | Delaware Basin Divestiture | Forecast
Subsequent Event [Line Items]
Federal tax expense		0
Sold | Delaware Basin Divestiture | Minimum | Forecast
Subsequent Event [Line Items]
State and local tax expense		7,000,000
Sold | Delaware Basin Divestiture | Maximum | Forecast
Subsequent Event [Line Items]
State and local tax expense		$ 11,000,000
Subsequent event
Subsequent Event [Line Items]
Quarterly base dividend declared (usd per share) | $ / shares	$ 0.62
Dividends declared (usd per share) | $ / shares	$ 3.02
Subsequent event | Sold | Delaware Basin Divestiture
Subsequent Event [Line Items]
Cash proceeds	$ 3,250,000,000
Subsequent event | Sold | Delaware Basin Divestiture | Minimum
Subsequent Event [Line Items]
Gain (loss) on sale	(900,000,000)
Subsequent event | Sold | Delaware Basin Divestiture | Maximum
Subsequent Event [Line Items]
Gain (loss) on sale	$ (1,100,000,000)
Subsequent event | Sold | Laredo Petroleum, Inc.
Subsequent Event [Line Items]
Cash proceeds			$ 160,000,000
Gain (loss) on sale			$ 5,000,000
Acres | a												20
Shares received (in shares) | shares			960
Total consideration												$ 230,000,000