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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jan. 07, 2016 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Nov. 16, 2017
Stockholders' Equity Note [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of treasury stock (in shares) |  |  |  |  |  |  |  |  |  |  | 594,974 | 776,126 |  |  |
Shares withheld for tax withholding obligations for the vesting of restricted stock awards (in shares) |  |  |  |  |  |  |  |  |  |  | 305,828 | 202,670 |  |  |
Additional shares authorized for Repurchase under the Stock Repurchase Program (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000
Remaining number of shares authorized to be repurchased (in shares) |  | 2,677,564 |  |  |  |  |  |  |  |  | 2,677,564 |  |  |  |
MaxAmountOfTenderOfferForRepurchaseOfShares | $ 125,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Price | $ 23.75 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased and Retired During Period, Shares | 6,027,062 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchase of common stock | $ 143,100 |  |  |  |  |  |  |  |  |  |  | $ 144,263 |  |  |
Transaction Costs Related to Tender Offer | 1,100 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Long-term debt | $ 104,400 | $ 104,400 |  |  |  |  | $ 104,400 |  |  |  | $ 104,400 | 104,400 |  |  |
Payments of Dividends [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends declared per share of common stock (in dollars per share) |  | $ 1.150 | [1] | $ 0.150 | $ 0.150 | $ 0.125 | $ 0.125 | $ 0.125 | $ 0.125 | $ 0.110 |  |  |  |  |
Dividends paid |  |  |  |  |  |  |  |  |  |  | $ 65,768 | $ 20,599 | $ 21,153 |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Special dividend, per share |  | $ 1.00 |  |  |  |  |  |  |  |  |  |  |  |  |
Special dividend |  | $ 41,700 |  |  |  |  |  |  |  |  |  |  |  | $ 50,700 |
Preferred stock, authorized (in shares) |  | 20,000,000 |  |  |  |  | 20,000,000 |  |  |  | 20,000,000 | 20,000,000 |  |  |
Preferred Stock, Value, Issued |  | $ 0 |  |  |  |  | $ 0 |  |  |  | $ 0 | $ 0 |  |  |
[1] | (1) Includes a $1.00 per share special dividend.

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