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v3.10.0.1

Consolidated Statement of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands | Total | Common Stock | Additional Paid-In Capital | Retained Earnings | Accumulated Other Comprehensive Loss | Treasury Stock
--- | --- | --- | --- | --- | --- | ---
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Cumulative effect of new accounting principle in period of adoption | $ 274 |  | $ 0 | $ 624 |  |
Net income | 31,189 |  |  |  |  |
Balance, shares at Dec. 31, 2017 |  | 32,332 |  |  |  | 615
Balance, value at Dec. 31, 2017 | 531,719 | $ 323 | 271,957 | 274,562 | $ (4,366) | $ (10,757)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Net income | 31,189 |  |  |  |  |
Foreign currency translation adjustment | (1,677) |  |  |  | (1,677) |
Adjustment to retirement benefit liability, net of taxes of $(4) | (10) |  |  |  | (10) |
Adjustment to post employment health care benefit liability, net of taxes of $25 | 63 |  |  |  | 63 |
Stock compensation expense | 4,828 |  | 4,828 |  |  |
Stock options exercised, shares |  | 34 |  |  |  |
Stock options exercised | 526 | $ 0 | 526 |  |  |
Issuance of restricted stock (in shares) |  | 2 |  |  |  |
Issuance of restricted stock | 0 | $ 0 | 0 |  |  |
Net settlement of restricted stock units, shares |  | 387 |  |  |  | 152
Net settlement of restricted stock units | (6,016) | $ 4 | (4) |  |  | $ (6,016)
Balance, shares at Jun. 30, 2018 |  | 32,755 |  |  |  | 767
Balance, value at Jun. 30, 2018 | $ 560,896 | $ 327 | $ 277,307 | $ 306,375 | (6,340) | $ (16,773)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  |  |  | $ (350) |

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