Equity Incentive Plans (Summary of Stock Option Activity) (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2019 $ / shares shares
Equity Incentive Plans
Shares, Balance Beginning | shares	1,275,380
Shares, Granted | shares	301,066
Shares, Exercised | shares	(27,382)
Shares, Forfeited/Cancelled | shares	(102,450)
Shares, Balance Ending | shares	1,446,614	1,275,380
Vested and expected to vest at September 30, 2020 | shares	1,446,614
Exercisable at September 30, 2020 | shares	425,114
Weighted Average Exercise Price, Outstanding Beginning | $ / shares	$ 7.61
Weighted Average Exercise Price, Granted | $ / shares	3.57
Weighted Average Exercise Price, Exercised | $ / shares	3.15
Weighted Average Exercise Price, Forfeited/Cancelled | $ / shares	6.35
Weighted Average Exercise Price, Outstanding Ending | $ / shares	6.79	$ 7.61
Weighted Average Exercise Price, Vested or expected to vest at September 30, 2020 | $ / shares	6.79
Weighted Average Exercise Price, Exercisable at September 30, 2020 | $ / shares	$ 15.18
Weighted Average Remaining Contractual Term (Years), Outstanding	8 years 3 months 18 days	8 years 9 months 22 days
Weighted Average Remaining Contractual Term (Years), Vested or expected to vest at September 30, 2020	8 years 3 months 18 days
Weighted Average Remaining Contractual Term (Years), Exercisable at September 30, 2020	6 years 11 months 9 days
Aggregate Intrinsic Value, Exercised | $	$ 14,000
Aggregate Intrinsic Value, Outstanding Ending | $	47,000
Aggregate Intrinsic Value, Vested or expected to vest at September 30, 2020 | $	47,000
Aggregate Intrinsic Value, Exercisable at September 30, 2020 | $	$ 11,000