Business Segment and Geographic Information (Details) - USD ($)		3 Months Ended			9 Months Ended
		Sep. 30, 2020		Sep. 30, 2019	Sep. 30, 2020		Sep. 30, 2019
Revenue:
Revenue		$ 2,975,000,000		$ 5,550,000,000	$ 11,208,000,000		$ 17,217,000,000
Operating income (loss):
Impairments and other charges		(133,000,000)	[1]	0	(3,353,000,000)	[1]	(308,000,000)	[1]
Operating income		142,000,000		536,000,000	(2,340,000,000)		1,204,000,000
Interest expense, net of interest income		(122,000,000)		(141,000,000)	(380,000,000)		(428,000,000)
Other, net		(21,000,000)		(23,000,000)	(92,000,000)		(61,000,000)
Income (loss) from continuing operations before income taxes		(1,000,000)		372,000,000	(2,980,000,000)		715,000,000
Loss on early extinguishment of debt		0		0	(168,000,000)	[2]	0
Long-term Debt, Excluding Current Maturities		1,500,000,000			1,500,000,000
Completion and Production
Revenue:
Revenue		1,574,000,000		3,506,000,000	6,029,000,000		10,973,000,000
Operating income (loss):
Impairments and other charges		(90,000,000,000)			(2,100,000,000)		(127,000,000)
Operating income		212,000,000		446,000,000	713,000,000		1,284,000,000
Drilling and Evaluation
Revenue:
Revenue		1,401,000,000		2,044,000,000	5,179,000,000		6,244,000,000
Operating income (loss):
Impairments and other charges		(40,000,000)			(1,200,000,000)		(153,000,000)
Operating income		105,000,000		150,000,000	452,000,000		418,000,000
Total operations
Revenue:
Revenue		2,975,000,000		5,550,000,000	11,208,000,000		17,217,000,000
Operating income (loss):
Operating income		317,000,000		596,000,000	1,165,000,000		1,702,000,000
Corporate and other
Operating income (loss):
Operating income	[3]	(42,000,000)		$ (60,000,000)	(152,000,000)		(190,000,000)
Corporate and Other [Member]
Operating income (loss):
Impairments and other charges		$ (3,000,000)			$ (44,000,000)		$ (28,000,000)

[1] For the three months ended September 30, 2020, amount includes approximately $90 million attributable to Completion and Production, $40 million attributable to Drilling and Evaluation, and $3 million attributable to Corporate and other. For the nine months ended September 30, 2020, amount includes $2.1 billion attributable to Completion and Production, $1.2 billion attributable to Drilling and Evaluation, and $44 million attributable to Corporate and other. For the nine months ended September 30, 2019, amount includes $127 million attributable to Completion and Production, $153 million attributable to Drilling and Evaluation, and $28 million attributable to Corporate and other. See Note 2 for further discussion on these impairments and other charges. There were no impairments and other charges recorded during the three months ended September 30, 2019.

[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. See Note 6 for further discussion on this charge.

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