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Common Stock - Share Based Compensation Table (Details) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  | 6 Months Ended
--- | --- | --- | --- | --- | ---
Jun. 12, 2019 | May 06, 2019 | Apr. 29, 2019 | Feb. 21, 2019 | Jun. 30, 2019
February 2019 ASR |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares |  |  | 4,525,592 | 31,908,831 | 36,434,423
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  | $ 19.21
Total |  |  |  |  | $ 700
May 2019 ASR |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares | 1,561,249 | 7,455,732 |  |  | 9,016,981
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  | $ 22.18
Total |  |  |  |  | $ 200
Accelerated Share Repurchase Program |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of shares |  |  |  |  | 45,451,404
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  | $ 19.80
Total |  |  |  |  | $ 900

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