v3.7.0.1

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] | AOCI Attributable to Parent [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 |  |  |
Net loss | (8,932) |  |  |  |  | (8,932)
Unrealized gain on short-term investments | 476 |  |  |  | 476 |
Changes in pension plan assets and benefit obligations | 1 |  |  |  | 1 |
Amortization of unearned stock-based compensation | 1,485 |  |  | 1,485 |  |
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 |  | 121 |  |  |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares | (503) | $ (3) |  | (500) |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, Shares |  | (27) |  |  |  |
Retirement of treasury stock | 0 | $ 0 | $ 0 | 0 | 0 | 0
Retirement of treasury stock, shares |  | (8) |  |  |  |
Balance at Mar. 31, 2016 | 619,537 | $ 1,278 | $ 291 | 305,869 | (90) | 312,189
Balance, Shares at Mar. 31, 2016 |  | 12,771 | 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 |  |  |
Net loss | (15,248) |  |  |  |  | (15,248)
Unrealized gain on short-term investments | 104 |  |  |  | 104 |
Changes in pension plan assets and benefit obligations | (1) |  |  |  | (1) |
Amortization of unearned stock-based compensation | 552 |  |  | 552 |  |
Issuance of non-voting common stock (upon vesting of restricted stock units) | 2 | $ 2 |  |  |  |
Issuance of non-voting common stock (upon vesting of restricted stock units), shares |  | 27 |  |  |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares | (101) | $ (1) |  | (100) |  |
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, Shares |  | (9) |  |  |  |
Cumulative effect adjustment of unrecognized tax benefits | 1,028 |  |  |  |  | 1,028
Balance at Mar. 31, 2017 | $ 586,114 | $ 1,279 | $ 291 | $ 304,698 | $ (375) | $ 280,221
Balance, Shares at Mar. 31, 2017 |  | 12,797 | 2,906 |  |  |

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