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Goodwill and Other Intangible Assets - Schedule of other intangible assets by asset class (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 4,013 | $ 3,397
Accumulated Amortization and Impairment | 2,280 | 1,507
Net Carrying Amount | 1,733 | 1,890
Customer related and contract based |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 2,550 | 2,023
Accumulated Amortization and Impairment | 1,415 | 1,198
Net Carrying Amount | 1,135 | 825
Tradenames |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 1,047 | 1,027
Accumulated Amortization and Impairment | 533 | 7
Net Carrying Amount | 514 | 1,020
Technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 416 | 347
Accumulated Amortization and Impairment | 332 | 302
Net Carrying Amount | $ 84 | 45
Reclassified gross carrying amount of finite lived intangibles |  | 29
Reclassified accumulated amortization of finite lived intangibles |  | $ 7

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- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph ((a)(1),(b)) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275 + Details
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