Segmented Information - Schedule of Segment Information for Reporting Segments (Parenthetical) (Detail) $ in Millions	Dec. 31, 2018 USD ($)
Power & Vision [Member]
Segment Reporting Information [Line Items]
Net assets held for sale	$ 541

Fair value portion of assets classified as held for sale.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258

Name:	us-gaap_AssetsHeldForSaleLongLivedFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant