Stock-Based Compensation - Restricted Stock Awards (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Weighted Average Grant-Date Fair Value
Stock based compensation expenses	$ 98,000	$ 433,000	$ (82,000)	$ 197,000
Restricted stock awards
Weighted Average Grant-Date Fair Value
Vesting period			20 months
Restricted stock awards - performance based awards
Number of Shares
Unvested at beginning of period (in shares)			7,118	13,345
Forfeited (in shares)			(6,227)	(6,227)
Unvested at end of period (in shares)	891	7,118	891	7,118
Weighted Average Grant-Date Fair Value
Unvested at beginning of period (in dollars per share)			$ 62.70	$ 62.70
Forfeited (in dollars per share)			62.70	62.70
Unvested at end of period (in dollars per share)	$ 62.70	$ 62.70	$ 62.70	$ 62.70
Unvested, number of shares (in shares)	891	7,118	891	7,118
Forfeited (in shares)			(6,227)	(6,227)
Stock based compensation expenses	$ 0	$ 0	$ (391,000)	$ (390,000)
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	1,042
Forfeited (in shares)			(5,774)	(20,134)
Unvested at end of period (in shares)	125,000	31,146	125,000	31,146
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	52.91
Forfeited (in dollars per share)			19.00	26.18
Unvested at end of period (in dollars per share)	$ 1.47	$ 12.87	$ 1.47	$ 12.87
Unvested, number of shares (in shares)	125,000	31,146	125,000	31,146
Forfeited (in shares)			(5,774)	(20,134)
Stock based compensation expenses	$ 25,554	$ 78,000	$ 37,417	$ 182,000

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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