Stock-Based Compensation - Service Based Restricted Stock Units (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Weighted Average Grant-Date Fair Value
Stock based compensation expenses	$ 176,000	$ 361,000	$ 94,000	$ 558,000
Restricted stock units - service based awards
Number of Shares
Unvested at beginning of period (in shares)			29,289	24,136
Granted (in shares)			125,000	28,186
Vested (in shares)			(23,515)	(20,134)
Forfeited (in shares)			(5,774)	(1,073)
Unvested at end of period (in shares)	125,000	31,115	125,000	31,115
Weighted Average Grant-Date Fair Value
Unvested at beginning of period (in dollars per share)			$ 12.87	$ 28.60
Granted (in dollars per share)			1.47	9.90
Vested (in dollars per share)			11.33	26.18
Forfeited (in dollars per share)			19.00	52.91
Unvested at end of period (in dollars per share)	$ 1.47	$ 12.87	$ 1.47	$ 12.87
Stock based compensation expenses	$ 46,193	$ 81,000	$ 83,607	$ 263,000
Unrecognized stock-based compensation expense	$ 100,000		$ 100,000
Unrecognized stock-based compensation expense, weighted average remaining term (in years) (less than)			1 year
Restricted stock units - service based awards \| Minimum
Weighted Average Grant-Date Fair Value
Vesting period			1 year
Restricted stock units - service based awards \| Maximum
Weighted Average Grant-Date Fair Value
Vesting period			3 years

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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