v3.20.4

Earnings Per Share (Narrative) (Details) - USD ($) shares in Millions, $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |  |  |
Repurchase of common stock |  | $ 5,498 | $ 2,417 | $ 609
Repurchase of common stock (in shares) |  | 142.0 |  |
Stock Repurchase Program |  |  |  |
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items] |  |  |  |
Repurchase of common stock | $ 4,000 |  |  |
Repurchase of common stock (in shares) | 104.8 |  |  |

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