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Shareholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions | 3 Months Ended |
--- | --- | ---
Jun. 30, 2019 | Mar. 31, 2019
Class of Stock [Line Items] |  |
Shares repurchased in period (in shares) | 1.8 |
Shares repurchased, weighted average price per share | $ 13.79 |
First Quarter 2019 Repurchase Program |  |
Class of Stock [Line Items] |  |
Authorized repurchase amount |  | $ 200
Second Quarter 2018 Repurchase Program |  |
Class of Stock [Line Items] |  |
Remaining authorized repurchase amount |  | $ 25

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