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Share Repurchases (Details) - USD ($) shares in Millions | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Oct. 31, 2020 | Dec. 31, 2019 | Mar. 31, 2019
Class of Stock [Line Items] |  |  |  |  |  |  |
Payments for repurchase of common stock |  |  | $ 1,800,000,000 | $ 6,279,100,000 |  |  |
December 2019 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  | $ 5,000,000,000 |
Repurchase of common stock, at cost, shares |  | 4.5 |  | 16.7 |  |  |
Payments for repurchase of common stock |  | $ 1,300,000,000 |  | $ 5,000,000,000 |  |  |
2020 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  | $ 5,000,000,000
Repurchase of common stock, at cost, shares |  |  |  | 4.1 |  |  |
Payments for repurchase of common stock |  |  |  | $ 1,300,000,000 |  |  |
October 2020 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  | $ 5,000,000,000 |  |
Repurchase of common stock, at cost, shares | 2.2 |  | 6.0 |  |  |  |
Payments for repurchase of common stock | $ 750,000,000 |  | $ 1,800,000,000 |  |  |  |
Amount remaining under 2019 Share Repurchase Program | $ 2,800,000,000 |  | $ 2,800,000,000 |  |  |  |

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