Revenue (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) Division	Mar. 31, 2020 USD ($)
Disaggregation of Revenue [Line Items]
Number of business segments \| Division	2
Revenue	$ 3,451	$ 5,037
Revenue, Performance Obligation, Description of Timing	one year
North America [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 1,404	2,460
Latin America [Member]
Disaggregation of Revenue [Line Items]
Revenue	535	516
Europe/Africa/CIS [Member]
Disaggregation of Revenue [Line Items]
Revenue	634	831
Middle East/Asia [Member]
Disaggregation of Revenue [Line Items]
Revenue	878	1,230
Completion And Production [Member]
Disaggregation of Revenue [Line Items]
Revenue	1,870	2,962
Drilling And Evaluation [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 1,581	$ 2,075
Minimum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Payment Terms	20
Maximum [Member]
Disaggregation of Revenue [Line Items]
Revenue, Performance Obligation, Description of Payment Terms	60
Revenue Benchmark [Member] \| UNITED STATES
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	39.00%	47.00%

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

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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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