Revenue (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) Division Countries	Dec. 31, 2019 USD ($) Countries	Dec. 31, 2018 USD ($) Countries
Disaggregation of Revenue [Line Items]
Number of business segments \| Division	2
Maximum Percentage Revenue from One Geographic Segment	10.00%	10.00%	10.00%
Number of Countries Exceed Revenue Threshold \| Countries	1	1	1
Revenue, Performance Obligation, Description of Timing	one year
Revenue	$ 14,445	$ 22,408	$ 23,995
North America [Member]
Disaggregation of Revenue [Line Items]
Revenue	5,731	11,884	14,431
Latin America [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,668	2,364	2,065
Europe/Africa/CIS [Member]
Disaggregation of Revenue [Line Items]
Revenue	2,813	3,285	2,945
Middle East/Asia [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 4,233	4,875	4,554
Minimum
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Payment Terms	20
Maximum
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Payment Terms	60 days
Completion and Production
Disaggregation of Revenue [Line Items]
Revenue	$ 7,839	14,031	15,973
Drilling and Evaluation
Disaggregation of Revenue [Line Items]
Revenue	$ 6,606	$ 8,377	$ 8,022
Revenue Benchmark [Member] \| UNITED STATES
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	38.00%	51.00%	58.00%

The maximum percentage of revenue from one geographic segment for the periods presented.

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The number of business segments into which the company's operations are divided.

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The number of countries that exceed the revenue threshold of 10%.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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Description of payment terms in contract with customer. Includes, but is not limited to, timing of payment, existence of financing component, variability of consideration and constraint on variable consideration.

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Description of timing for satisfying performance obligation in contract with customer. Includes, but is not limited to, as services are rendered, and upon shipment, delivery or completion of service.

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