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Goodwill - Changes in Carrying Amount of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 123	$ 116
Foreign currency translation	(2)	7
Goodwill, Ending Balance	121	123
Microcontrollers and Digital ICs Group (MDG) [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	121	114
Foreign currency translation	(2)	7
Goodwill, Ending Balance	119	121
Analog, MEMS & Sensors Group (AMS) [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	2	2
Goodwill, Ending Balance	$ 2	$ 2

X

- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
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- Definition

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.

+ References

No definition available.

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
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-Section 50
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