Impairment and Other Charges (Details) - USD ($)		3 Months Ended		12 Months Ended
		Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restructuring Cost and Reserve [Line Items]
Long-lived asset impairments				$ 2,629,000,000	$ 1,603,000,000	$ 0
Inventory costs and write-downs				505,000,000	458,000,000	0
Severance				384,000,000	172,000,000	0
Joint ventures				0	154,000,000	0
Other				281,000,000	119,000,000	0
Total impairments and other charges	[1]			$ 3,799,000,000	2,506,000,000	265,000,000
Decline in WTI oil spot price		25.00%		31.00%
Impairment of real estate properties				$ 616,000,000
Impairment of drilling-services equipment				297,000,000
Impairment of hydraulic fracturing equipment				1,000,000,000.0	759,000,000
Impairment of real estate facilities					215,000,000
Impairment of legacy drilling equipment					243,000,000
Impairment of intangible assets				131,000,000	98,000,000
Impairment of right-of-use assets associated with operating leases				191,000,000	139,000,000
Impairment of other fixed assets				$ 394,000,000	148,000,000
Decline in US average rig count				54.00%
Decline in International average rig count				25.00%
Decline in global rig count				38.00%
Impairments and other charges				$ 3,799,000,000	2,506,000,000	265,000,000
Impairment of hydraulic fracturing equipment				1,000,000,000.0	759,000,000
Impairment of legacy drilling equipment					243,000,000
Impairment of real estate facilities					215,000,000
Impairment of right-of-use assets associated with operating leases				191,000,000	139,000,000
Impairment of intangible assets				131,000,000	98,000,000
Impairment of other fixed assets				394,000,000	148,000,000
Arithmetic Average [Member]
Restructuring Cost and Reserve [Line Items]
WTI oil spot price		$ 43		39
Maximum
Restructuring Cost and Reserve [Line Items]
WTI oil spot price			$ 63
Minimum
Restructuring Cost and Reserve [Line Items]
WTI oil spot price		$ 48	$ 21
Completion and Production
Restructuring Cost and Reserve [Line Items]
Total impairments and other charges				2,400,000,000	1,600,000,000
Drilling and Evaluation
Restructuring Cost and Reserve [Line Items]
Total impairments and other charges				1,400,000,000	849,000,000
VENEZUELA
Restructuring Cost and Reserve [Line Items]
Venezuela investment write-down				$ 0	$ 0	265,000,000
Total impairments and other charges	[1]					$ 265,000,000
UNITED STATES | Revenue Benchmark [Member]
Restructuring Cost and Reserve [Line Items]
Concentration Risk, Percentage				38.00%	51.00%	58.00%

[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.