Stockholders' Equity - Stock Options and a Summary of Activity (Details)	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Number of Options
Outstanding at beginning of period (in shares) | shares	221,450
Granted (in shares) | shares	72,120
Canceled/forfeited (in shares) | shares	(4,459)
Expired (in shares) | shares	(1,500)
Outstanding at end of period (in shares) | shares	287,611
Vested and expected to vest at period end (in shares) | shares	228,312
Exercisable at period end (in shares) | shares	62,154
Weighted Average Exercise Price Per Share
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 3.45
Granted (in dollars per share) | $ / shares	5.51
Canceled/forfeited (in dollars per share) | $ / shares	2.77
Expired (in dollars per share) | $ / shares	53.50
Outstanding at end of period (in dollars per share) | $ / shares	3.71
Vested and expected to vest at period end (in dollars per share) | $ / shares	3.68
Exercisable at period end (in dollars per share) | $ / shares	$ 4.25
Weighted Average Remaining Contractual Life (in years)
Outstanding at end of period	8 years 10 months 24 days
Vested and expected to vest at period end	8 years 9 months 18 days
Exercisable at period end	8 years 1 month 6 days