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v3.6.0.2

Consolidated statements of changes in stockholders' equity - USD ($) $ in Thousands | Total | Common Stock | Additional paid in capital | Treasury Shares | Warrants | Retained earnings | Accumulated other comprehensive income / (loss) | Total common Stockholders’ equity | Non controlling Interest
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Balance at Dec. 31, 2013 | $ 1,330,966 | $ 964 | $ 826,028 | $ (30,249) | $ 687 | $ 525,140 | $ 7,785 | $ 1,330,355 | $ 611
Balance (in shares) at Dec. 31, 2013 |  | 96,306,753 |  | (3,585,098) |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures (in shares) |  | 70,179 |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures | (679) | $ 1 | (680) |  |  |  |  | (679) |
Stock based compensation expense | 18,770 |  | 18,770 |  |  |  |  | 18,770 |
Exercised stock options (in shares) |  | 1,108,045 |  |  |  |  |  |  |
Exercised stock options | 9,185 | $ 11 | 9,174 |  |  |  |  | 9,185 |
Exercise of warrants (in shares) |  | 248,189 |  |  |  |  |  |  |
Exercise of warrants |  | $ 2 | 685 |  | (687) |  |  |  |
Issuance of performance shares (in shares) |  | 21,603 |  |  |  |  |  |  |
Issuance of performance shares | (70) |  | (70) |  |  |  |  | (70) |
Shares issued in employee stock purchase plan (in shares) |  | 110,509 |  |  |  |  |  |  |
Shares issued in employee stock purchase plan | 2,665 | $ 1 | 2,664 |  |  |  |  | 2,665 |
Treasury stock (in shares) |  |  |  | (4,523,885) |  |  |  |  |
Treasury stock | (102,231) |  |  | $ (102,231) |  |  |  | (102,231) |
Excess tax benefits | 7,742 |  | 7,742 |  |  |  |  | 7,742 |
Change in pension liability | (1,110) |  |  |  |  |  | (1,110) | (1,110) |
Currency translation adjustment | (43,694) |  |  |  |  |  | (43,636) | (43,636) | (58)
Net income (loss) | 174,377 |  |  |  |  | 174,365 |  | 174,365 | 12
Balance at Dec. 31, 2014 | 1,395,921 | $ 979 | 864,313 | $ (132,480) | 0 | 699,505 | (36,961) | 1,395,356 | 565
Balance (in shares) at Dec. 31, 2014 |  | 97,865,278.000 |  | (8,108,983) |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures (in shares) |  | 157,577 |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures | (874) | $ 1 | (875) |  |  |  |  | (874) |
Stock based compensation expense | 21,675 |  | 21,675 |  |  |  |  | 21,675 |
Exercised stock options (in shares) |  | 419,363 |  |  |  |  |  |  |
Exercised stock options | 3,622 | $ 4 | 3,618 |  |  |  |  | 3,622 |
Issuance of performance shares (in shares) |  | 17,282 |  |  |  |  |  |  |
Issuance of performance shares | (22) |  | (22) |  |  |  |  | (22) |
Shares issued in employee stock purchase plan (in shares) |  | 146,402 |  |  |  |  |  |  |
Shares issued in employee stock purchase plan | 2,549 | $ 2 | 2,547 |  |  |  |  | 2,549 |
Treasury stock (in shares) |  |  |  | (36,819) |  |  |  |  |
Treasury stock | (838) |  |  | $ (838) |  |  |  | (838) |
Excess tax benefits | (8) |  | (8) |  |  |  |  | (8) |
Change in pension liability | 46 |  |  |  |  |  | 46 | 46 |
Currency translation adjustment | (45,270) |  |  |  |  |  | (45,133) | (45,133) | (137)
Net income (loss) | (119,384) |  |  |  |  | (119,353) |  | (119,353) | (31)
Balance at Dec. 31, 2015 | 1,257,417 | $ 986 | 891,248 | $ (133,318) | 0 | 580,152 | (82,048) | 1,257,020 | 397
Balance (in shares) at Dec. 31, 2015 |  | 98,605,902.000 |  | (8,145,802) |  |  |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures (in shares) |  | 670,769 |  |  |  |  |  |  |
Restricted stock issuance, net of forfeitures | (1,045) | $ 6 | (1,051) |  |  |  |  | (1,045) |
Stock based compensation expense | $ 20,535 |  | 20,535 |  |  |  |  | 20,535 |
Exercised stock options (in shares) | 151,000 | 151,335 |  |  |  |  |  |  |
Exercised stock options | $ 1,712 | $ 2 | 1,710 |  |  |  |  | 1,712 |
Issuance of performance shares (in shares) |  | 42,443 |  |  |  |  |  |  |
Issuance of performance shares | (47) | $ 1 | (48) |  |  |  |  | (47) |
Shares issued in employee stock purchase plan (in shares) |  | 186,679 |  |  |  |  |  |  |
Shares issued in employee stock purchase plan | 1,978 | $ 2 | 1,976 |  |  |  |  | 1,978 |
Equity offering (in shares) |  | 4,025,000 |  |  |  |  |  |  |
Equity offering | 85,078 | $ 40 | 85,038 |  |  |  |  | 85,078 |
Treasury stock (in shares) |  |  |  | (29,161) |  |  |  |  |
Treasury stock | (623) |  |  | $ (623) |  |  |  | (623) |
Excess tax benefits | (1,239) |  | (1,239) |  |  |  |  | (1,239) |
Change in pension liability | (335) |  |  |  |  |  | (335) | (335) |
Currency translation adjustment | (45,722) |  |  |  |  |  | (45,854) | (45,854) | 132
Net income (loss) | (81,948) |  |  |  |  | (81,978) |  | (81,978) | 30
Balance at Dec. 31, 2016 | $ 1,235,761 | $ 1,037 | $ 998,169 | $ (133,941) | $ 0 | $ 498,174 | $ (128,237) | $ 1,235,202 | $ 559
Balance (in shares) at Dec. 31, 2016 |  | 103,682,128.000 |  | (8,174,963) |  |  |  |  |

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