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Goodwill and Intangible Assets - Goodwill Business Segments (Details) - USD ($) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2020 | Dec. 31, 2017
Goodwill [Line Items] |  |  |  |
Goodwill | $ 14,653 | $ 14,544 | $ 14,653 | $ 14,533
Acquisitions | 107 | 33 |  |
Reductions in goodwill related to divestitures | (1) | (17) |  |
Other adjustments | 3 | (5) |  |
Credit Card |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill | 5,088 | 5,060 | 5,088 | 5,032
Acquisitions | 25 | 33 |  |
Reductions in goodwill related to divestitures | 0 | 0 |  |
Other adjustments | 3 | (5) |  |
Consumer Banking |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill | 4,645 | 4,600 | 4,645 | 4,600
Acquisitions | 46 | 0 |  |
Reductions in goodwill related to divestitures | (1) | 0 |  |
Other adjustments | 0 | 0 |  |
Commercial Banking |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill | 4,920 | 4,884 | $ 4,920 | $ 4,901
Acquisitions | 36 | 0 |  |
Reductions in goodwill related to divestitures | 0 | (17) |  |
Other adjustments | $ 0 | $ 0 |  |

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