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Preferred and Common Stock - Details For the Share Repurchases (Details) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
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Nov. 21, 2019 | Nov. 20, 2019 | Nov. 19, 2019 | Nov. 18, 2019 | Oct. 03, 2019 | Aug. 08, 2019 | Jun. 12, 2019 | May 06, 2019 | Apr. 29, 2019 | Feb. 21, 2019 | Dec. 31, 2019
February 2019 ASR |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [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 |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [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
August 2019 ASR |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares |  |  |  |  | 983,107 | 6,791,172 |  |  |  |  | 7,774,279
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  |  |  |  |  |  |  | $ 25.73
Total |  |  |  |  |  |  |  |  |  |  | $ 200
Share Repurchases Program November 2019 |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares | 400,681 | 370,000 | 428,000 | 428,000 |  |  |  |  |  |  | 1,626,681
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  |  |  |  |  |  |  | $ 30.74
Total |  |  |  |  |  |  |  |  |  |  | $ 50
Accelerated Share Repurchase Program |  |  |  |  |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares |  |  |  |  |  |  |  |  |  |  | 54,852,364
Treasury stock acquired, average price per share (in usd per share) |  |  |  |  |  |  |  |  |  |  | $ 20.97
Total |  |  |  |  |  |  |  |  |  |  | $ 1,150

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