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Goodwill and Other Intangible Assets - Schedule of other intangible assets by asset class (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | $ 3,673 | $ 3,658 |
Accumulated Amortization and Impairment | 2,890 | 2,509 |
Net Carrying Amount | 783 | 1,149 |
Amortization and impairment of intangible assets | 392 | 593 | $ 704
Customer related and contract based |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 2,264 | 2,240 |
Accumulated Amortization and Impairment | 1,600 | 1,444 |
Net Carrying Amount | 664 | 796 |
Tradenames |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 1,029 | 1,027 |
Accumulated Amortization and Impairment | 956 | 740 |
Net Carrying Amount | 73 | 287 |
Technology |  |  |
Finite-Lived Intangible Assets [Line Items] |  |  |
Gross Carrying Amount | 380 | 391 |
Accumulated Amortization and Impairment | 334 | 325 |
Net Carrying Amount | $ 46 | $ 66 |

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