Charges and Credits - Additional Information (Detail) - USD ($)	3 Months Ended							9 Months Ended	12 Months Ended
	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2017	Dec. 31, 2017
Charges And Credits [Line Items]
Charges and credits, pre tax								$ 723,000,000
Charges and credits	$ 0		$ 0			$ 50,000,000		667,000,000
Promissory note in exchange of accounts receivable						$ 700,000,000
Promissory note term						3 years
Promissory note interest rate						6.50%
Charge relating to one-time mandatory tax on previously deferred foreign earnings				$ 410,000,000					$ 410,000,000
Tax credits resulting from remeasurement of net deferred tax liabilities				334,000,000
US tax reform
Charges And Credits [Line Items]
Charges and credits				$ 76,000,000
US tax reform | Tax Year2018
Charges And Credits [Line Items]
Reduced corporate income tax rate									21.00%
Impairments and Other | Headcount Reductions
Charges And Credits [Line Items]
Charges and credits, pre tax		$ 184,000,000
Charges and credits		$ 164,000,000
Merger and Integration
Charges And Credits [Line Items]
Charges and credits, pre tax								213,000,000
Charges and credits								169,000,000
Merger and Integration | Cameron International Corporation
Charges And Credits [Line Items]
Charges and credits					$ 49,000,000	$ 81,000,000
Merger and Integration | Merger-related employee benefits | Cameron International Corporation
Charges And Credits [Line Items]
Charges and credits							$ 82,000,000
Promissory Note Fair Value Adjustment and Other
Charges And Credits [Line Items]
Charges and credits, pre tax								510,000,000
Charges and credits						$ 460,000,000		$ 498,000,000