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Stockholders' Equity - Additional Information (Detail) - USD ($) | 3 Months Ended
--- | ---
Mar. 31, 2017 | Mar. 31, 2016
Class of Stock [Line Items] |  |
Common stock dividend paid | $ 0.16 | $ 0.16
Purchase price of common stock repurchased on open market | $ 110,000,000 | $ 200,000,000
Authorized share repurchased program remaining available amount | $ 490,000,000 |
Common Stock [Member] |  |
Class of Stock [Line Items] |  |
Closing price of common stock | $ 14.76 |
Common Stock Shares Outstanding [Member] |  |
Class of Stock [Line Items] |  |
Common shares repurchased | 7,363,292 | 19,210,281

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