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v3.8.0.1

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 |  |
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 | 8,352 |  |  |  |  |
Foreign currency translation adjustment | 110 |  |  |  | 110 |
Adjustment to retirement benefit liability, net of taxes of $(2) | (5) |  |  |  | (5) |
Adjustment to post employment health care benefit liability, net of taxes of $12 | 32 |  |  |  | 32 |
Stock compensation expense | 2,097 |  | 2,097 |  |  |
Stock options exercised, shares |  | 13 |  |  |  |
Stock options exercised | 226 | $ 0 | 226 |  |  |
Net settlement of restricted stock units, shares |  | 53 |  |  |  | 24
Net settlement of restricted stock units | (850) | $ 1 | (1) |  |  | $ (850)
Balance, shares at Mar. 31, 2018 |  | 32,398 |  |  |  | 639
Balance, value at Mar. 31, 2018 | $ 541,955 | $ 324 | $ 274,279 | $ 283,538 | (4,579) | $ (11,607)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  |  |  | $ (350) |

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