Consolidated Statements of Equity - USD ($) $ in Millions	Total	Common Stock	Additional Paid-in Capital	Treasury Stock	Retained Earnings
Beginning balance (in shares) at Dec. 31, 2019		165,547,000
Beginning balance at Dec. 31, 2019	$ 12,136	$ 2	$ 9,161	$ (1,069)	$ 4,042
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(91)				(91)
Exercise of long-term incentive stock options (in shares)		8,000
Exercise of long-term incentive stock options	0		(1)	1
Purchases of treasury stock (in shares)		(1,007,000)
Purchases of treasury stock	(122)			(122)
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		316,000
Vested compensation awards, net	0
Compensation costs included in net income	16		16
Net loss	291				291
Ending balance (in shares) at Mar. 31, 2020		164,864,000
Ending balance at Mar. 31, 2020	12,230	$ 2	9,176	(1,190)	4,242
Beginning balance (in shares) at Dec. 31, 2019		165,547,000
Beginning balance at Dec. 31, 2019	12,136	$ 2	9,161	(1,069)	4,042
Stock-based compensation costs:
Net loss	(243)
Ending balance (in shares) at Sep. 30, 2020		164,403,000
Ending balance at Sep. 30, 2020	11,598	$ 2	9,305	(1,235)	3,526
Beginning balance (in shares) at Mar. 31, 2020		164,864,000
Beginning balance at Mar. 31, 2020	12,230	$ 2	9,176	(1,190)	4,242
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(91)				(91)
Equity component	230		230
Capped call	(113)		(113)
Deferred tax provision	(25)		(25)
Purchases of treasury stock (in shares)		(592,000)
Purchases of treasury stock	(50)			(50)
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		4,000
Vested compensation awards, net	0
Compensation costs included in net income	17		17
Net loss	(449)				(449)
Ending balance (in shares) at Jun. 30, 2020		164,276,000
Ending balance at Jun. 30, 2020	11,749	$ 2	9,285	(1,240)	3,702
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(91)				(91)
Exercise of long-term incentive stock options (in shares)		62,000
Exercise of long-term incentive stock options	6		(1)	7
Purchases of treasury stock (in shares)		(19,000)
Purchases of treasury stock	(2)			(2)
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		84,000
Vested compensation awards, net	0
Compensation costs included in net income	21		21
Net loss	(85)				(85)
Ending balance (in shares) at Sep. 30, 2020		164,403,000
Ending balance at Sep. 30, 2020	11,598	$ 2	9,305	(1,235)	3,526
Beginning balance (in shares) at Dec. 31, 2020		164,477,000
Beginning balance at Dec. 31, 2020	11,569	$ 2	9,323	(1,234)	3,478
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(122)				(122)
Equity component	(202)		(230)		28
Deferred tax provision	44		50		(6)
Exercise of long-term incentive stock options (in shares)		55,000
Exercise of long-term incentive stock options	6		(2)	8
Purchases of treasury stock (in shares)		(99,000)
Purchases of treasury stock	(13)			(13)
Shares issued or reissued for acquisition (in shares)		51,655,000
Shares issued or reissued for Parsley Energy, Inc. ("Parsley") acquisition	6,882		5,644	1,238
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		623,000
Vested compensation awards, net	0
Compensation costs included in net income	19		19
Compensation costs included in net loss associated with Parsley acquisition	33		33
Net loss	(70)				(70)
Ending balance (in shares) at Mar. 31, 2021		216,711,000
Ending balance at Mar. 31, 2021	18,146	$ 2	14,837	(1)	3,308
Beginning balance (in shares) at Dec. 31, 2020		164,477,000
Beginning balance at Dec. 31, 2020	$ 11,569	$ 2	9,323	(1,234)	3,478
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Equity component			(230)		28
Deferred tax provision			50		(6)
Exercise of long-term incentive stock options (in shares)	55,173
Stock-based compensation costs:
Net loss	$ 1,355
Ending balance (in shares) at Sep. 30, 2021		244,122,000
Ending balance at Sep. 30, 2021	23,193	$ 2	19,104	0	4,087
Beginning balance (in shares) at Mar. 31, 2021		216,711,000
Beginning balance at Mar. 31, 2021	18,146	$ 2	14,837	(1)	3,308
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(138)				(138)
Purchases of treasury stock (in shares)		(2,000)
Purchases of treasury stock	(1)			(1)
Shares issued or reissued for acquisition (in shares)		27,187,000
Shares issued or reissued for Parsley Energy, Inc. ("Parsley") acquisition	4,234		4,234
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		63,000
Vested compensation awards, net	0
Compensation costs included in net income	17		17
Net loss	380				380
Ending balance (in shares) at Jun. 30, 2021		243,959,000
Ending balance at Jun. 30, 2021	22,638	$ 2	19,088	(2)	3,550
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dividends declared	(508)				(508)
Exercise of long-term incentive stock options (in shares)		53,000
Exercise of long-term incentive stock options	5		(2)	7
Purchases of treasury stock (in shares)		(34,000)
Purchases of treasury stock	(5)			(5)
Stock-based compensation costs:
Vested compensation awards, net or issued awards (in shares)		144,000
Vested compensation awards, net	0
Compensation costs included in net income	18		18
Net loss	1,045				1,045
Ending balance (in shares) at Sep. 30, 2021		244,122,000
Ending balance at Sep. 30, 2021	$ 23,193	$ 2	$ 19,104	$ 0	$ 4,087