Company and Nature of Business - Additional Information (Details) - USD ($)		1 Months Ended		3 Months Ended		6 Months Ended
	May 08, 2020	Jan. 31, 2020	Jul. 31, 2019	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Cash flow from operations						$ (12,958,000)	$ (14,422,000)
Accumulated deficit				$ 262,280,000		262,280,000		$ 248,630,000
Proceeds from capital contribution					$ 11,500,000
Proceeds from private offering of common stock		$ 7,500,000	$ 13,800,000			7,475,000
PPP Loan
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Amount of loan received	$ 1,133,600
PPP Loan | Five Star Bank
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Amount of loan received	$ 1,100,000
Open Market Sale Agreement
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Proceeds from the sale of shares				$ 1,200,000
Open Market Sale Agreement | Common Stock
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of common stock sold				317,688
Stock Purchase Agreement | Keystone Capital Partners, LLC
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Stock purchase program number of shares agree to purchase						$ 5,000,000
Proceeds from the sale of shares				$ 1,100,000
Stock Purchase Agreement | Common Stock | Keystone Capital Partners, LLC
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Number of common stock sold				324,424