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Other Intangible Assets - Other Intangible Assets (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
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Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | $ 1,228 | $ 1,145
Accumulated Amortization | (1,019) | (950)
Net Cost | 209 | 195
Technologies & Licenses [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | 668 | 618
Accumulated Amortization | (566) | (534)
Net Cost | 102 | 84
Contractual Customer Relationships [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | 5 | 4
Accumulated Amortization | (5) | (4)
Purchased and Internally Developed Software [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | 440 | 407
Accumulated Amortization | (383) | (347)
Net Cost | 57 | 60
In-process R&D [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | 50 | 51
Net Cost | 50 | 51
Other Intangible Assets [Member] |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Cost | 65 | 65
Accumulated Amortization | $ (65) | $ (65)

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- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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