Income Taxes - Additional Information (Details) - USD ($)	3 Months Ended								12 Months Ended
	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
Net loss	$ (10,363,000)	$ (12,692,000)	$ (13,972,000)	$ (11,636,000)	$ (10,258,000)	$ (8,026,000)	$ (6,976,000)	$ (7,585,000)	$ (48,663,000)	$ (32,845,000)	$ (47,339,000)
Income tax benefit									0
Valuation allowance	49,744,000				35,216,000				49,744,000	35,216,000	$ 51,800,000
Valuation allowances period increase (decrease)									14,500,000	(16,600,000)
Accrued interest and penalties related to uncertain tax positions	0				0				$ 0	0
Income tax examination, description									The federal, state and foreign income tax returns are generally subject to tax examinations for the tax years ended December 31, 2018 through December 31, 2021.
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	188,200,000				140,900,000				$ 188,200,000	140,900,000
Operating loss carryforwards with an indefinite life	154,300,000								154,300,000
Operating loss carryforwards subject to expiration	33,900,000								$ 33,900,000
Operating loss carryforwards expiration period									2037
Federal | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	2,100,000				500,000				$ 2,100,000	500,000
Tax credit carryforward expiration period									2041
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	96,300,000				51,100,000				$ 96,300,000	51,100,000
Operating loss carryforwards expiration period									2041
State | Research and Development
Operating Loss Carryforwards [Line Items]
Tax credit carryforward	$ 500,000				$ 100,000				$ 500,000	$ 100,000
Tax credit carryforward expiration period									2036