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Goodwill and Other Intangible Assets - Schedule of other intangible assets by asset class (Details) - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | $ 3,658 | $ 4,013
Accumulated Amortization and Impairment | 2,509 | 2,280
Net Carrying Amount | 1,149 | 1,733
Customer related and contract based |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 2,240 | 2,550
Accumulated Amortization and Impairment | 1,444 | 1,415
Net Carrying Amount | 796 | 1,135
Tradenames |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 1,027 | 1,047
Accumulated Amortization and Impairment | 740 | 533
Net Carrying Amount | 287 | 514
Technology |  |
Finite-Lived Intangible Assets [Line Items] |  |
Gross Carrying Amount | 391 | 416
Accumulated Amortization and Impairment | 325 | 332
Net Carrying Amount | $ 66 | $ 84

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