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Stock-Based Compensation - Additional Information (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation		$ 99,000	$ 106,000
Unrecognized compensation costs related to non-vested stock options	$ 55,000	$ 55,000
Period over which compensation costs related to non-vested stock options recognize		2 years
Tax benefit from recording non-cash expense relates to options granted to employees		$ 0
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units granted		0	0
Stock-based compensation		$ 55,000	$ 46,000
Unrecognized compensation costs related to non-vested stock options	$ 88,000	88,000
Restricted Stock Units (RSUs) \| Board of Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock units vested	3,000
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation		$ 44,000	$ 60,000
Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of options granted		0	0