Acquisitions/Divestitures - Goodwill (Details) - USD ($) $ in Millions |
3 Months Ended | |||
|---|---|---|---|---|
Mar. 31, 2020 |
Dec. 31, 2019 |
Jul. 09, 2019 |
Dec. 31, 2018 |
|
| Acquisitions | ||||
| Goodwill | $ 57,517 | $ 58,222 | $ 36,265 | |
| Expected percent of goodwill deductible for tax purposes | 7.00% | |||
| Red Hat, Inc. | ||||
| Acquisitions | ||||
| Goodwill | $ 23,100 | $ 23,137 | ||
| Cloud & Cognitive Software | Red Hat, Inc. | ||||
| Acquisitions | ||||
| Goodwill | 18,500 | |||
| Global Technology Services | Red Hat, Inc. | ||||
| Acquisitions | ||||
| Goodwill | 3,100 | |||
| Global Business Services | Red Hat, Inc. | ||||
| Acquisitions | ||||
| Goodwill | 1,100 | |||
| Systems | Red Hat, Inc. | ||||
| Acquisitions | ||||
| Goodwill | $ 400 |