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Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands | Total | Common Stock | Retained Earnings | Accumulated Other Comprehensive Income (Loss)
--- | --- | --- | --- | ---
Beginning Balance at Dec. 31, 2014 | $ 908,924 | $ 323,596 | $ 587,862 | $ (2,534)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |
Net income | 86,795 |  | 86,795 |
Other comprehensive loss, net of tax | 2,940 |  |  | 2,940
Common stock transactions: |  |  |  |
Common shares purchased and retired | (20,647) | (20,647) |  |
Common shares issued | 0 |  |  |
Non-vested common shares issued | 0 |  |  |
Non-vested common shares forfeited or canceled | 0 |  |  |
Stock options exercised, net of shares tendered in payment of option price and income tax withholding amounts | 3,369 | 3,369 |  |
Tax benefit of stock-based compensation | 1,443 | 1,443 |  |
Stock-based compensation expense | 3,959 | 3,959 |  |
Cash dividends declared: |  |  |  |
Common (per share) | (36,290) |  | (36,290) |
Ending Balance at Dec. 31, 2015 | 950,493 | 311,720 | 638,367 | 406
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |
Net income | 95,636 |  | 95,636 |
Other comprehensive loss, net of tax | (8,534) |  |  | (8,534)
Common stock transactions: |  |  |  |
Common shares purchased and retired | (26,854) | (26,854) |  |
Common shares issued | 0 |  |  |
Non-vested common shares issued | 0 |  |  |
Non-vested common shares forfeited or canceled | 0 |  |  |
Stock options exercised, net of shares tendered in payment of option price and income tax withholding amounts | 4,683 | 4,683 |  |
Tax benefit of stock-based compensation | 2,146 | 2,146 |  |
Stock-based compensation expense | 4,376 | 4,376 |  |
Cash dividends declared: |  |  |  |
Common (per share) | (39,353) |  | (39,353) |
Ending Balance at Dec. 31, 2016 | 982,593 | 296,071 | 694,650 | (8,128)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |
Net income | 106,521 |  | 106,521 |
Other comprehensive loss, net of tax | (3,835) |  |  | (3,835)
Common stock transactions: |  |  |  |
Common shares purchased and retired | (1,348) | (1,348) |  |
Non-vested common shares issued | 0 |  |  |
Non-vested common shares forfeited or canceled | 0 |  |  |
Stock options exercised, net of shares tendered in payment of option price and income tax withholding amounts | 2,431 | 2,431 |  |
Stock-based compensation expense | 3,868 | 3,868 |  |
Cash dividends declared: |  |  |  |
Common (per share) | (48,583) |  | (48,583) |
Ending Balance at Dec. 31, 2017 | 1,427,616 | 686,991 | $ 752,588 | $ (11,963)
Common stock transactions: |  |  |  |
Common Stock, Value, Issued | $ 385,969 | $ 385,969 |  |

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