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Shareholders' Equity - Schedule of Stock Repurchases (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended | 96 Months Ended
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020
Equity, Class of Treasury Stock [Line Items] |  |  |
Total repurchase cost | $ 463 | $ 101 |
2012 - Share Repurchase Program |  |  |
Equity, Class of Treasury Stock [Line Items] |  |  |
Shares purchased (in shares) | 2.2 | 0.6 | 130.9
Average price per share of stock repurchased (in dollars per share) | $ 212.78 | $ 161.16 |
Total repurchase cost | $ 461 | $ 100 | $ 13,400
Additional associated costs | 2 | 1 |
Total costs recorded to retained earnings | $ 463 | $ 101 |

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