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Stock-Based Compensation - Summary of Unvested Stock Options (Details) - USD ($) | 9 Months Ended
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Sep. 30, 2018 | Sep. 30, 2017
Shares |  |
Unvested, beginning of period (in shares) | 48,581 |
Vested (in shares) | (26,549) |
Canceled/Forfeited (in shares) | (1,167) |
Unvested, end of period (in shares) | 20,865 |
Weighted Average Grant Date Fair Value Per Share |  |
Unvested, weighted average grant date fair value, beginning of period (in USD per share) | $ 11.41 |
Canceled/Forfeited, weighted average grant date fair value (in USD per share) | 11.93 |
Vested, weighted average grant date fair value (in USD per share) | 10.97 |
Unvested, weighted average grant date fair value, end of period (in USD per share) | $ 11.93 |
Stock Options |  |
Weighted Average Grant Date Fair Value Per Share |  |
Unrecognized compensation cost related to unvested options | $ 158,759 |
Unrecognized compensation cost related to awards, weighted average period for recognition | 2 years |
Share-based compensation expense | $ 127,055 | $ 286,500

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested options awarded to employees as compensation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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