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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Equity Plans - Description (Details) - shares	9 Months Ended
Equity Plans - Description (Details) - shares	Sep. 30, 2018	May 31, 2018
2016 Equity Incentive Plan
Equity Plans
Number of shares available for issuance	201,579
2018 Inducement Plan
Equity Plans
Expiration period	10 years
Number of shares authorized		750,000
Number of shares available for issuance	645,000
Stock options - employees, consultants, directors \| 2016 Equity Incentive Plan
Equity Plans
Expiration period	10 years
Options to Purchase Common Stock \| 2016 Equity Incentive Plan
Equity Plans
Vesting period	4 years
Non Employee Director Initial Stock Options \| 2016 Equity Incentive Plan
Equity Plans
Vesting period	3 years
Nonemployee Director Annual Refresher Stock Options \| 2016 Equity Incentive Plan
Equity Plans
Vesting period	1 year
Nonemployee Consultant Options \| 2016 Equity Incentive Plan \| Minimum
Equity Plans
Vesting period	1 year
Nonemployee Consultant Options \| 2016 Equity Incentive Plan \| Maximum
Equity Plans
Vesting period	4 years