Organization and Description of Business (Details) - USD ($)		1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 06, 2022	Jul. 31, 2022	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021	Oct. 31, 2021
Nature of Operations
Accumulated deficit			$ 411,105,000		$ 411,105,000		$ 387,117,000
Cash, cash equivalents and marketable securities			$ 13,000,000.0		13,000,000.0
Working capital deficit					$ 10,300,000
Common stock that can be purchased with warrants (in shares)			1,242,813		1,242,813			333,333
General and Administrative Expense			$ 3,026,000	$ 3,852,000	$ 7,023,000	$ 7,653,000
Revision of Prior Period, Error Correction, Adjustment [Member]
Nature of Operations
General and Administrative Expense				$ (263,000)		$ (363,000)
Subsequent Event | Series B Pre-funded Warrants
Nature of Operations
Common stock that can be purchased with warrants (in shares)	7,518,334
Public offering
Nature of Operations
Proceeds from issuance of common stock and warrants	$ 22,200,000
Issuance of common stock (in shares)	19,148,332	7,518,334
Common stock that can be purchased with warrants (in shares)	7,518,334	38,296,664						333,333
Public offering | Series B Pre-funded Warrants
Nature of Operations
Warrant shares issued	7,518,334