Segment Information - Sales Revenues by Geographic Area Table (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenue from External Customer [Line Items]
Sales revenues	$ 14,044		$ 8,447
Oil and Gas [Member]
Revenue from External Customer [Line Items]
Sales revenues	13,070	$ 10,969	8,447
Oil and Gas [Member] \| United States [Member]
Revenue from External Customer [Line Items]
Sales revenues	10,659	9,176	7,049
Oil and Gas [Member] \| Algeria [Member]
Revenue from External Customer [Line Items]
Sales revenues	1,596	1,249	1,103
Oil and Gas [Member] \| Other International [Member]
Revenue from External Customer [Line Items]
Sales revenues	$ 815	$ 544	$ 295

Amount, excluding 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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration