Summary of Significant Accounting Policies - Net Loss Per Share (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) segment shares	Dec. 31, 2018 shares	Nov. 30, 2019 USD ($)	Jan. 01, 2019 USD ($)
Antidilutive common stock equivalents excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from the calculation of diluted net loss per share (in shares) | shares	6,979,581	4,635,838
Segment Information
Number of operating segments | segment	1
Operating Lease, Right-of-Use Asset	$ 2,349		$ 1,700
Operating Lease, Liability, Current	$ 1,225
Operating Lease, Weighted Average Discount Rate, Percent			7.49%
Stock options
Antidilutive common stock equivalents excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from the calculation of diluted net loss per share (in shares) | shares	785,832	433,389
Common stock warrants
Antidilutive common stock equivalents excluded from computation of diluted net loss per share
Anti-dilutive securities excluded from the calculation of diluted net loss per share (in shares) | shares	6,193,749	4,202,449
Restatement adjustment | AccountingStandardsUpdate201602Member
Segment Information
Operating Lease, Right-of-Use Asset				$ 1,900
Operating Lease, Liability, Current				$ 1,900
Operating Lease, Weighted Average Discount Rate, Percent				7.49%