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Common Stock (Details) - USD ($) |  |  | 2 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 29, 2019 | Feb. 21, 2019 | Apr. 29, 2019 | Apr. 26, 2019 | Mar. 31, 2019 | Feb. 19, 2019 | Mar. 31, 2018
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |
Common stock outstanding (in shares) |  |  |  |  | 453,000,000 |  | 483,000,000
Accelerated Share Repurchase Program |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |
Accelerated stock repurchase program, shares to be repurchased, dollar amount |  |  |  |  |  | $ 700,000,000 |
Shares acquired |  | 31,908,831 |  |  |  |  |
Subsequent Event |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |
Common stock outstanding (in shares) | 448,629,078 |  | 448,629,078 |  |  |  |
Subsequent Event | Accelerated Share Repurchase Program |  |  |  |  |  |  |
Accelerated Share Repurchases [Line Items] |  |  |  |  |  |  |
Shares acquired | 4,525,592 |  | 36,434,423 |  |  |  |
Purchase price of shares repurchased under ASR agreement (in dollars per share) |  |  | $ 19.21 |  |  |  |
Stock repurchase program, shares authorized |  |  |  | $ 300,000,000 |  |  |

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