Business Segment and Geographic Information (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue:
Revenue		$ 3,860	$ 2,975	$ 11,018	$ 11,208
Operating income (loss):
Impairments and other charges	[1]	12	133	12	3,353
Operating income		446	142	1,250	(2,340)
Interest expense, net of interest income		(116)	(122)	(361)	(380)
Other, net		(14)	(21)	(55)	(92)
Income (loss) from continuing operations before income taxes		316	(1)	834	(2,980)
Loss on early extinguishment of debt		0	0	0	168	[2]
Total operations
Operating income (loss):
Operating income		508	317	1,423	1,165
Completion and Production
Revenue:
Revenue		2,136	1,574	6,054	6,029
Operating income (loss):
Impairments and other charges		42	90	42	2,100
Completion and Production | Total operations
Operating income (loss):
Operating income		322	212	891	713
Drilling and Evaluation
Revenue:
Revenue		1,724	1,401	4,964	5,179
Operating income (loss):
Impairments and other charges		9	40	9	1,200
Drilling and Evaluation | Total operations
Operating income (loss):
Operating income		186	105	532	452
Corporate and Other [Member]
Operating income (loss):
Impairments and other charges		(39)	3	(39)	44
Operating income	[3]	$ (50)	$ (42)	$ (161)	$ (152)

[1] For the three and nine months ended September 30, 2021, amount includes a $42 million charge attributable to Completions and Production, a $9 million charge attributable to Drilling and Evaluation, and a $39 million net gain attributable to Corporate and other. For the three and nine months ended September 30, 2020, amount includes $90 million and $2.1 billion attributable to Completion and Production, $40 million and $1.2 billion attributable to Drilling and Evaluation, and $3 million and $44 million attributable to Corporate and other, respectively.

[2] For the nine months ended September 30, 2020, amount includes a $168 million loss on extinguishment of debt related to the early repurchase of senior notes.

[3] Includes certain expenses not attributable to a business segment, such as costs related to support functions and corporate executives, and also includes amortization expense associated with intangible assets recorded as a result of acquisitions.