v3.8.0.1

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands | Total | Common Stock | Additional Paid-In Capital | Treasury Stock | Retained Earnings
--- | --- | --- | --- | --- | ---
Beginning balance (shares) at Dec. 31, 2014 |  | 26,657,000 |  |  |
Beginning balance at Dec. 31, 2014 | $ 493,187 | $ 267 | $ 50,598 | $ (88,134) | $ 530,456
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |
Net income | 47,605 |  |  |  | 47,605
Exercise of stock options (shares) |  | 58,000 |  |  |
Exercise of stock options | 1,728 |  | 1,728 |  |
Tax benefit on exercise of stock options | 40 |  | 40 |  |
Stock-based compensation | 658 |  | 658 |  |
Dividend declared—$0.08 per share | (1,657) |  |  |  | (1,657)
Purchase of treasury stock | (2,922) |  |  | (2,922) |
Ending balance (shares) at Dec. 31, 2015 |  | 26,715,000 |  |  |
Ending balance at Dec. 31, 2015 | 538,639 | $ 267 | 53,024 | (91,056) | 576,404
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |
Net income | 33,839 |  |  |  | 33,839
Exercise of stock options (shares) |  | 48,000 |  |  |
Exercise of stock options | 1,437 | $ 1 | 1,436 |  |
Tax benefit on exercise of stock options | 60 |  | 60 |  |
Stock-based compensation | 791 |  | 791 |  |
Dividend declared—$0.08 per share | (1,657) |  |  |  | (1,657)
Ending balance (shares) at Dec. 31, 2016 |  | 26,763,000 |  |  |
Ending balance at Dec. 31, 2016 | 573,109 | $ 268 | 55,311 | (91,056) | 608,586
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |
Net income | $ 67,017 |  |  |  | 67,017
Exercise of stock options (shares) | 91,500 | 91,000 |  |  |
Exercise of stock options | $ 1,927 | $ 1 | 1,926 |  |
Stock-based compensation (shares) |  | 5,000 |  |  |
Stock-based compensation | 955 |  | 955 |  |
Dividend declared—$0.08 per share | (1,663) |  |  |  | (1,663)
Ending balance (shares) at Dec. 31, 2017 |  | 26,859,000 |  |  |
Ending balance at Dec. 31, 2017 | $ 641,345 | $ 269 | $ 58,192 | $ (91,056) | $ 673,940

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