Stock-Based Compensation - Restricted Stock Awards (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Weighted Average Grant-Date Fair Value
Stock based compensation expenses	$ 943,000	$ 475,000
Restricted stock awards
Number of Shares
Outstanding at beginning of period (in shares)	146,800	146,800
Forfeited (in shares)	(68,500)
Outstanding at end of period (in shares)	78,300	146,800
Weighted Average Grant-Date Fair Value
Outstanding at beginning of period (in dollars per share)	$ 5.70	$ 5.70
Forfeited (in dollars per share)	5.70
Outstanding at end of period (in dollars per share)	$ 5.70	$ 5.70
Vesting period	20 months
Unvested restricted stock awards (in shares)	78,300	146,800
Stock based compensation expenses	$ 0	$ 0
Unrecognized stock-based compensation expenses	$ 0
Restricted stock awards - Performance based awards
Number of Shares
Outstanding at end of period (in shares)	78,300
Weighted Average Grant-Date Fair Value
Unvested restricted stock awards (in shares)	78,300
Stock based compensation expenses	$ (390,000)	$ 0

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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