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Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Mar. 31, 2019 | Sep. 30, 2018 | Sep. 30, 2016
Class of Stock [Line Items] |  |  |  |  |  |  |
Payments for repurchase of common stock |  |  | $ 3,057.3 | $ 3,000.0 |  |  |
2019 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  | $ 5,000.0 |  |
Repurchase of common stock, at cost, shares |  |  | 3.9 |  |  |  |
Payments for repurchase of common stock |  |  | $ 909.9 |  |  |  |
Amount remaining under 2019 Share Repurchase Program | $ 4,100.0 |  | $ 4,100.0 |  |  |  |
2018 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  | $ 3,500.0 |
Repurchase of common stock, at cost, shares | 6.5 |  | 8.9 |  |  |  |
Payments for repurchase of common stock | $ 1,500.0 |  | $ 2,100.0 |  |  |  |
2016 Share Repurchase Program |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  | $ 5,000.0
Repurchase of common stock, at cost, shares |  | 9.6 |  | 10.5 |  |  |
Payments for repurchase of common stock |  | $ 2,750.0 |  | $ 3,000.0 |  |  |

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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585 + Details
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