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STOCK-BASED COMPENSATION - 2015 EIP Stock Options and Other (Details) - 2015 EIP Plan - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  |  | 12 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 25, 2020 | Nov. 05, 2019 | Mar. 04, 2019 | Feb. 27, 2018 | Mar. 23, 2017 | Oct. 15, 2016 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Mar. 22, 2017 | Jun. 26, 2015
Stock options |  |  |  |  |  |  |  |  |  |  |
Aggregate number of shares of common stock available for awards |  |  |  |  | 2,750,000 |  |  |  |  | 400,000 | 400,000
Nonemployee Directors |  |  |  |  |  |  |  |  |  |  |
Additional disclosures |  |  |  |  |  |  |  |  |  |  |
Maximum annual limit for grants (in shares) |  |  |  |  | 500,000 |  |  |  |  |  |
Other Individuals |  |  |  |  |  |  |  |  |  |  |
Additional disclosures |  |  |  |  |  |  |  |  |  |  |
Maximum annual limit for grants (in shares) |  |  |  |  | 1,000,000 |  |  |  |  |  |
Stock Options |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |  |  |
Vesting percentage of awards | 33.33% |  | 33.33% | 33.33% |  |  |  |  |  |  |
Vesting period | 3 years |  | 3 years | 3 years |  |  |  |  |  |  |
Unrecognized compensation cost |  |  |  |  |  |  |  |  |  |  |
Unamortized compensation cost |  |  |  |  |  |  | $ 490 |  |  |  |
Future amortization of stock based compensation |  |  |  |  |  |  |  |  |  |  |
2021 |  |  |  |  |  |  | 367 |  |  |  |
2022 |  |  |  |  |  |  | 111 |  |  |  |
2023 |  |  |  |  |  |  | $ 12 |  |  |  |
Number of Options |  |  |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in shares) |  |  |  |  |  |  | 322,279 | 166,942 | 88,667 |  |
Granted (in shares) | 344,568 |  | 240,540 | 122,608 |  |  | 344,568 | 240,540 | 122,608 |  |
Exercisable (in shares) |  |  |  |  |  |  | (119,923) | (85,203) | (44,333) |  |
Forfeited (in shares) |  |  |  |  |  |  | (3,378) |  |  |  |
Outstanding at end of period (in shares) |  |  |  |  |  |  | 543,546 | 322,279 | 166,942 |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in dollars per share) |  |  |  |  |  |  | $ 9.41 | $ 13.01 | $ 11.13 |  |
Granted (in dollars per share) | $ 7.06 |  | $ 8.065 | $ 13.365 |  |  | 7.06 | 8.33 | 13.69 |  |
Exercisable (in dollars per share) |  |  |  |  |  |  | 9.87 | 12.36 | 11.13 |  |
Forfeited (in dollars per share) |  |  |  |  |  |  | 8.07 |  |  |  |
Outstanding at end of period (in dollars per share) |  |  |  |  |  |  | 7.83 | 9.41 | 13.01 |  |
Weighted Average Fair Value |  |  |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in dollars per share) |  |  |  |  |  |  | 4.72 | 7.25 | 6.41 |  |
Granted (in dollars per share) | $ 2.01 |  | $ 3.76 | $ 7.55 |  |  | 2.01 | 3.76 | 7.55 |  |
Exercisable (in dollars per share) |  |  |  |  |  |  | 5.05 | 6.96 | 6.41 |  |
Forfeited (in dollars per share) |  |  |  |  |  |  | 3.76 |  |  |  |
Outstanding at end of period (in dollars per share) |  |  |  |  |  |  | 2.94 | $ 4.72 | $ 7.25 |  |
Weighted Average Exercise Price Of Outstanding Options |  |  |  |  |  |  | $ 8.86 |  |  |  |
Options Outstanding, Weighted Average Remaining Contractual Life |  |  |  |  |  |  | 4 years 8 months 19 days |  |  |  |
Options Exercisable, Number of options |  |  |  |  |  |  | 293,792 |  |  |  |
Options Exercisable, Weighted Average Exercise Price |  |  |  |  |  |  | $ 10.78 |  |  |  |
Options Exercisable, Weighted Average Remaining Contractual Life |  |  |  |  |  |  | 3 years 3 days |  |  |  |
Aggregate fair value | $ 693 |  | $ 904 | $ 926 |  |  |  |  |  |  |
Stock options outstanding - nonvested and exercisable |  |  |  |  |  |  | 837,338 | 496,148 |  |  |
Assumptions and Methodology |  |  |  |  |  |  |  |  |  |  |
Weighted average volatility rate (as a percent) | 53.91% |  | 55.23% | 71.94% |  |  |  |  |  |  |
Risk-free interest rate ( as a percent) | 1.41% |  | 2.49% | 2.53% |  |  |  |  |  |  |
Dividend rate ( as a percent) | 7.13% |  | 0.00% | 0.00% |  |  |  |  |  |  |
Expected life (in years) | 4 years |  | 4 years | 4 years |  |  |  |  |  |  |
Stock Options | General and Administrative Expense |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |  |  |
Amortization expense |  |  |  |  |  |  | $ 787 | $ 850 | $ 731 |  |
Stock Options | Exercise Price - $13.365 |  |  |  |  |  |  |  |  |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) |  | $ 13.365 |  |  |  |  |  |  |  |  |
Stock Options | Exercise Price - $8.065 |  |  |  |  |  |  |  |  |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) |  | 8.065 |  |  |  |  |  |  |  |  |
Stock Options | Exercise Price - $7.06 |  |  |  |  |  |  |  |  |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) | $ 7.06 |  |  |  |  |  |  |  |  |  |
Stock Options | John C. Wobensmith |  |  |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |  |  |
Vesting percentage of awards |  |  |  |  | 33.33% |  |  |  |  |  |
Vesting period |  |  |  |  |  | 3 years |  |  |  |  |
Number of Options |  |  |  |  |  |  |  |  |  |  |
Granted (in shares) |  |  |  |  | 133,000 |  |  |  |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) |  | $ 10.805 |  |  |  |  |  |  |  |  |
Weighted Average Fair Value |  |  |  |  |  |  |  |  |  |  |
Granted (in dollars per share) |  |  |  |  | $ 6.41 |  |  |  |  |  |
Aggregate fair value |  |  |  |  | $ 853 |  |  |  |  |  |
Assumptions and Methodology |  |  |  |  |  |  |  |  |  |  |
Weighted average volatility rate (as a percent) |  |  |  |  | 79.80% |  |  |  |  |  |
Risk-free interest rate ( as a percent) |  |  |  |  | 1.68% |  |  |  |  |  |
Dividend rate ( as a percent) |  |  |  |  | 0.00% |  |  |  |  |  |
Expected life (in years) |  |  |  |  | 3 years 9 months 10 days |  |  |  |  |  |

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