Stockholders' Equity Share Repurchase Program (Details) - USD ($) $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Equity [Abstract] | |||
| Number of shares authorized to be repurchased under stock repurchase program (in shares) | 37,500,000 | ||
| Number of shares repurchased and retired to date (in shares) | 12,067,500 | ||
| Cost of shares repurchased and retired to date | $ 200,375 | ||
| Repurchase of common stock (in shares) | 0 | (4,010,000) | (6,832,150) |
| Repurchase of common stock | $ 0 | $ (61,307) | $ (115,174) |
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- Definition The number of shares repurchased and retired under a stock repurchase plan to date (as of period-end). No definition available.
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- Definition The value of shares repurchased and retired (dollar amount paid) under a stock repurchase plan to date (as of period-end). No definition available.
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- References No definition available.
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- Definition The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan. No definition available.
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- Definition Number of shares that have been repurchased and retired during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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