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Stock-Based Compensation - Summary of Unvested Stock Options (Details) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018
Shares |  |  |
Unvested, beginning of period (in shares) |  |  | 48,581
Vested (in shares) |  |  | (26,549)
Canceled/Forfeited (in shares) |  |  | (500)
Unvested, end of period (in shares) | 21,532 |  | 21,532
Weighted AverageGrant Date Fair Value Per Share |  |  |
Unvested, weighted average grant date fair value, beginning of period (in USD per share) |  |  | $ 11.41
Vested, weighted average grant date fair value (in USD per share) |  |  | 10.97
Canceled/Forfeited, weighted average grant date fair value (in USD per share) |  |  | 11.93
Unvested, weighted average grant date fair value, end of period (in USD per share) | $ 11.93 |  | $ 11.93
Stock Options |  |  |
Weighted AverageGrant Date Fair Value Per Share |  |  |
Unrecognized compensation cost related to unvested options | $ 192,000 |  | $ 192,000
Unrecognized compensation cost related to awards, weighted average period for recognition |  |  | 2 years
Share-based compensation expense | $ 97,140 | $ 207,560 |

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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://www.xbrl.org/2003/role/presentationRef -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=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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=96867065&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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested options awarded to employees as compensation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Number of non-vested options outstanding. + References No definition available. + Details
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