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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | Dec. 31, 2014 | Sep. 30, 2014 | Jun. 30, 2014 | Mar. 31, 2014 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Stockholders' Equity Note [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of treasury stock (in shares) |  |  |  |  |  |  |  |  |  | 1,244,433 | 580,804 |  |
Shares withheld for tax withholding obligations for the vesting of restricted stock awards (in shares) |  |  |  |  |  |  |  |  |  | 114,523 | 112,458 |  |
Remaining number of shares authorized to be repurchased (in shares) |  | 524,332 |  |  |  |  |  |  |  | 524,332 |  |  |
Payments of Dividends [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends declared per share of common stock (in dollars per share) |  | $ 0.22 | $ 0.22 | $ 0.22 | $ 0.19 |  | $ 0.19 | $ 0.19 | $ 0.17 |  |  |  |
Special dividends declared, per share of commong stock (in dollars per share) |  | $ 0.00 |  |  |  | $ 2.00 |  |  |  |  |  |  |
Payments of Ordinary Dividends, Common Stock |  |  |  |  |  |  |  |  |  | $ 21,153 | $ 69,493 | $ 17,386 |
Special dividend |  |  |  |  |  |  |  |  |  |  | $ 50,700 |  | $ 25,700
Total regular and special quarterly dIvidend declared, per share of common stock (in dollars per share) | [1] |  |  |  |  | $ 2.19 |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, authorized (in shares) |  | 20,000,000 |  |  |  | 20,000,000 |  |  |  | 20,000,000 | 20,000,000 |  |
Common stock purchase right per preferred stock share (in shares) |  |  |  |  |  |  |  |  |  | 1 |  |  |
Series A Junior Participating Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, authorized (in shares) |  | 600,000 |  |  |  |  |  |  |  | 600,000 |  |  |
[1] | 1) Includes a $2.00 per share special dividend

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