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Stockholders' Equity - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 28, 2019 | Sep. 30, 2018
Class of Stock [Line Items] |  |  |  |  |  |
Dividends per common share | $ 0.16 | $ 0.16 | $ 0.32 | $ 0.32 |  |
Common stock dividends paid | $ 37,000,000 | $ 42,000,000 | $ 76,000,000 | $ 85,000,000 |  |
Authorized share repurchased program amount |  |  |  |  |  | $ 500,000,000
Common Stock [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Closing price of common stock |  |  |  |  | $ 13.65 |
Authorized common share repurchased program remaining available amount | $ 207,000,000 |  | $ 207,000,000 |  |  |
Common Stock Shares Outstanding [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Common stock repurchased | 9,617,008 |  | 19,034,252 | 0 |  |
Purchase price of common stock repurchased on open market | $ 126,000,000 |  | $ 233,000,000 |  |  |

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