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Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Apr. 22, 2020 | Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Class of Stock [Line Items] |  |  |  |
Payments for repurchase of common stock |  | $ 2,220.2 | $ 655.8 |
December 2019 Share Repurchase Program |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  | $ 5,000.0
Repurchase of common stock, at cost, shares |  | 3.2 |  |
Payments for repurchase of common stock |  | $ 941.1 |  |
2019 Share Repurchase Program |  |  |  |
Class of Stock [Line Items] |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  | $ 5,000.0 |
Repurchase of common stock, at cost, shares |  | 4.1 |  |
Payments for repurchase of common stock |  | $ 1,300.0 |  |
Amount remaining under 2019 Share Repurchase Program |  | $ 2,800.0 |  |
Subsequent Event [Member] | 2019 Share Repurchase Program |  |  |  |
Class of Stock [Line Items] |  |  |  |
Repurchase of common stock, at cost, shares | 4.0 |  |  |
Payments for repurchase of common stock | $ 1,300.0 |  |  |

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