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Business Segments and Geographic Areas - Business Segments (Parenthetical) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Operating profit (loss)	$ (6,279)	$ 211	$ (277)
Goodwill Indefinite Lived And Finite Lived Intangible And Long Lived Tangible Assets | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	3,565
Goodwill Indefinite Lived And Finite Lived Intangible And Long Lived Tangible Assets | Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	1,865
Goodwill Indefinite Lived And Finite Lived Intangible And Long Lived Tangible Assets | Rig Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	389
Inventory Charges | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	130		4
Inventory Charges | Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	148		(6)
Inventory Charges | Rig Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	355		110
Voluntary Early Retirement Program | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	64
Voluntary Early Retirement Program | Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	30
Voluntary Early Retirement Program | Rig Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)	$ 37
Severance, Facility Closures And Other Items | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)		28
Non-operational Credits Elimination and Corporate Costs [Member] | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)		$ (18)
Severance And Facility Closures Cost | Wellbore Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)			18
Severance And Facility Closures Cost | Completion & Production Solutions [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)			32
Severance And Facility Closures Cost | Rig Technologies [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)			$ 20

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