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STOCK-BASED COMPENSATION - 2015 EIP Stock Options and Other (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | --- | --- | ---
Mar. 04, 2019 | Feb. 27, 2018 | Mar. 23, 2017 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Jun. 26, 2015
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 |  |  |  |  |  |
2015 EIP Plan |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |
Aggregate number of shares of common stock available for awards |  |  | 2,750,000 |  |  |  |  |  | 400,000
2015 EIP Plan | Stock Options |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |
Vesting percentage of awards | 33.00% | 33.33% |  |  |  |  |  |  |
Vesting period | 3 years | 3 years |  |  |  |  |  |  |
Unrecognized compensation cost |  |  |  |  |  |  |  |  |
Unamortized compensation cost |  |  |  | $ 1,030 |  | $ 1,030 |  |  |
Future amortization of stock based compensation |  |  |  |  |  |  |  |  |
Remainder of 2019 |  |  |  | 440 |  | 440 |  |  |
2020 |  |  |  | 431 |  | 431 |  |  |
2021 |  |  |  | 142 |  | 142 |  |  |
2022 |  |  |  | $ 17 |  | $ 17 |  |  |
Number of Options |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in shares) |  |  |  |  |  | 166,942 |  |  |
Granted (in shares) | 240,540 | 122,608 |  |  |  | 240,540 |  |  |
Exercisable (in shares) |  |  |  |  |  | (40,869) |  |  |
Outstanding at end of period (in shares) |  |  |  | 366,613 |  | 366,613 |  |  |
Weighted Average Exercise Price |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in dollars per share) |  |  |  |  |  | $ 13.01 |  |  |
Granted (in dollars per share) | $ 8.39 | $ 13.69 |  |  |  | 8.39 |  |  |
Exercisable (in dollars per share) |  |  |  |  |  | 13.69 |  |  |
Outstanding at end of period (in dollars per share) |  |  |  | $ 9.90 |  | 9.90 |  |  |
Weighted Average Fair Value |  |  |  |  |  |  |  |  |
Outstanding at beginning of period (in dollars per share) |  |  |  |  |  | 7.25 |  |  |
Granted (in dollars per share) | $ 3.76 | $ 7.55 |  |  |  | 3.76 |  |  |
Exercisable (in dollars per share) |  |  |  |  |  | 7.55 |  |  |
Outstanding at end of period (in dollars per share) |  |  |  | 4.93 |  | 4.93 |  |  |
Weighted Average Exercise Price Of Outstanding Options |  |  |  | $ 10.43 |  | $ 10.43 |  |  |
Options Outstanding, Weighted Average Remaining Contractual Life |  |  |  |  |  | 5 years 2 months 19 days |  |  |
Options Exercisable, Number of options |  |  |  | 129,535 |  | 129,535 |  |  |
Options Exercisable, Weighted Average Exercise Price |  |  |  | $ 11.94 |  | $ 11.94 |  |  |
Options Exercisable, Weighted Average Remaining Contractual Life |  |  |  |  |  | 3 years 26 days |  |  |
Aggregate fair value | $ 904 | $ 926 |  |  |  |  |  |  |
Stock options outstanding - nonvested and exercisable |  |  |  | 496,148 |  | 496,148 |  | 255,608 |
Assumptions and Methodology |  |  |  |  |  |  |  |  |
Weighted average volatility rate (as a percent) | 55.23% | 71.94% |  |  |  |  |  |  |
Risk-free interest rate ( as a percent) | 2.49% | 2.53% |  |  |  |  |  |  |
Dividend rate ( as a percent) | 0.00% | 0.00% |  |  |  |  |  |  |
Expected life (in years) | 4 years | 4 years |  |  |  |  |  |  |
2015 EIP Plan | Stock Options | General and Administrative Expense |  |  |  |  |  |  |  |  |
Stock options |  |  |  |  |  |  |  |  |
Amortization expense |  |  |  | $ 229 | $ 214 | $ 411 | $ 337 |  |
2015 EIP Plan | 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) |  |  | $ 11.13 |  |  |  |  |  |
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 11 days |  |  |  |  |  |

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