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Stockholders' Equity - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2016 | Mar. 31, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015
Class of Stock [Line Items] |  |  |  |  |
Common stock dividend paid | $ 0.16 | $ 0.16 | $ 0.16 | $ 0.32 | $ 0.32
Purchase price of common stock repurchased on open market | $ 175,000,000 |  | $ 300,000,000 | $ 375,000,000 | $ 600,000,000
Authorized share repurchased program remaining available amount | $ 380,000,000 |  |  | $ 380,000,000 |
Common Stock [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Closing price of common stock | $ 11.95 |  |  | $ 11.95 |
Common Stock Shares Outstanding [Member] |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Common shares repurchased | 13,579,381 |  | 15,190,685 | 32,789,662 | 29,844,520

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