Business Segment and Geographic Information (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue:
Revenue		$ 14,445	$ 22,408	$ 23,995
Operating income:
Total operating income (loss)		(2,436)	(448)	2,467
Impairments and other charges		3,799	2,506	265
Impairments and other charges	[1]	(3,799)	(2,506)	(265)
Interest expense, net of interest income		(505)	(569)	(554)
Other, net		(111)	(105)	(99)
Income (loss) before income taxes		(3,220)	(1,122)	1,814
Capital expenditures:
Total capital expenditures		728	1,530	2,026
Depreciation, depletion and amortization:
Total depreciation, depletion and amortization		1,058	1,625	1,606
Total assets:
Total assets		20,680	25,377
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net		4,325	7,310
Gain (Loss) on Extinguishment of Debt		(168)	0	0
Completion and Production
Revenue:
Revenue		7,839	14,031	15,973
Operating income:
Total operating income (loss)		995	1,671	2,278
Impairments and other charges		(2,400)	(1,600)
Capital expenditures:
Total capital expenditures		314	800	1,364
Depreciation, depletion and amortization:
Total depreciation, depletion and amortization		615	1,049	1,058
Total assets:
Total assets	[2]	7,924	11,894
Drilling and Evaluation
Revenue:
Revenue		6,606	8,377	8,022
Operating income:
Total operating income (loss)		569	642	745
Impairments and other charges		(1,400)	(849)
Capital expenditures:
Total capital expenditures		410	728	657
Depreciation, depletion and amortization:
Total depreciation, depletion and amortization		430	552	512
Total assets:
Total assets	[2]	6,371	8,059
Corporate and shared assets
Total assets:
Total assets	[3]	6,385	5,424
Total operations
Operating income:
Total operating income (loss)		1,564	2,313	3,023
Corporate and other
Operating income:
Total operating income (loss)	[4]	(201)	(255)	(291)
Impairments and other charges		(56)
Capital expenditures:
Total capital expenditures		4	2	5
Depreciation, depletion and amortization:
Total depreciation, depletion and amortization		13	$ 24	36
Corporate and Other [Member]
Operating income:
Impairments and other charges		$ (62)
VENEZUELA
Operating income:
Impairments and other charges	[1]			(265)
UNITED STATES | Property, Plant and Equipment [Member]
Property, Plant and Equipment [Abstract]
Concentration Risk, Percentage		49.00%	59.00%
North America [Member]
Revenue:
Revenue		$ 5,731	$ 11,884	14,431
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net		2,211	4,666
Latin America [Member]
Revenue:
Revenue		1,668	2,364	2,065
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net		544	754
Europe/Africa/CIS [Member]
Revenue:
Revenue		2,813	3,285	2,945
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net		602	772
Middle East/Asia [Member]
Revenue:
Revenue		4,233	4,875	$ 4,554
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment, Net		$ 968	$ 1,118

[1] Impairments and other charges are as follows:     -For the year ended December 31, 2020, amount includes approximately $2.4 billion attributable to Completion and Production, $1.4 billion attributable to Drilling and Evaluation, and $62 million attributable to Corporate and other. -For the year ended December 31, 2019, amount includes approximately $1.6 billion attributable to Completion and Production, $849 million attributable to Drilling and Evaluation, and $56 million attributable to Corporate and other.     -For the years ended December 31, 2018, we recorded aggregate charges of $265 million to write-down our investment in Venezuela.

[2] Assets associated with specific segments primarily include receivables, inventories, property, plant, and equipment, operating lease right-of-use assets, equity in and advances to related companies, and goodwill.

[3] Corporate and other primarily include cash and equivalents and deferred tax assets.

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