v3.8.0.1

Condensed Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands | Total | Non-Voting Common Stock [Member] | Voting Common Stock [Member] | Additional Paid-in Capital [Member] | Accumulated Other Comprehensive (Loss) Income [Member] | Retained Earnings [Member]
--- | --- | --- | --- | --- | --- | ---
Balance at Dec. 31, 2015 | $ 626,998 | $ 1,269 | $ 291 | $ 304,884 | $ (567) | $ 321,121
Balance, Shares at Dec. 31, 2015 |  | 12,685 | 2,906 |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Net loss | (9,622) |  |  |  |  | (9,622)
Unrealized gain on short-term investments | 294 |  |  |  | 294 |
Changes in pension plan assets and benefit obligations | 2 |  |  |  | 2 |
Amortization of unearned stock-based compensation | 4,334 |  |  | 4,334 |  |
Issuance of non-voting common stock (upon vesting of restricted stock units) | 12 | $ 12 |  |  |  |
Issuance of non-voting common stock (upon vesting of restricted stock units), shares |  | 128 |  |  |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares | (531) | $ (3) |  | (528) |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, Shares |  | (28) |  |  |  |
Retirement of treasury stock, shares |  | (8) |  |  |  |
Balance at Sep. 30, 2016 | 621,487 | $ 1,278 | $ 291 | 308,690 | (271) | 311,499
Balance, Shares at Sep. 30, 2016 |  | 12,777 | 2,906 |  |  |
Balance at Dec. 31, 2016 | 599,778 | $ 1,278 | $ 291 | 304,246 | (478) | 294,441
Balance, Shares at Dec. 31, 2016 |  | 12,779 | 2,906 |  |  |
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |
Net loss | (21,798) |  |  |  |  | (21,798)
Unrealized gain on short-term investments | 235 |  |  |  | 235 |
Changes in pension plan assets and benefit obligations | (1) |  |  |  | (1) |
Amortization of unearned stock-based compensation | 3,074 |  |  | 3,074 |  |
Issuance of non-voting common stock (upon vesting of restricted stock units) | 3 | $ 13 |  | (10) |  |
Issuance of non-voting common stock (upon vesting of restricted stock units), shares |  | 136 |  |  |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares | (258) | $ (2) |  | (256) |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, Shares |  | (22) |  |  |  |
Cumulative effect adjustment of unrecognized tax benefits | 1,028 |  |  |  |  | 1,028
Balance at Sep. 30, 2017 | $ 582,061 | $ 1,289 | $ 291 | $ 307,054 | $ (244) | $ 273,671
Balance, Shares at Sep. 30, 2017 |  | 12,893 | 2,906 |  |  |

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