Stock-Based Compensation - Performance Based Stock Options (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Weighted Average Exercise Price
Stock based compensation expenses	$ 361,000	$ 250,000	$ 558,000	$ (276,000)
Stock option awards - performance based awards
Number of Shares
Outstanding at the beginning of the period (in shares)			750,000	388,125
Expired (in shares)			(750,000)
Granted (in shares)				750,000
Forfeited (in shares)				(388,125)
Outstanding at the end of the period (in shares)	0	750,000	0	750,000
Exercisable at end of period (in shares)	0	0	0	0
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)			$ 2.20	$ 4.70
Expired (in dollar per share)			2.20
Granted (in dollars per share)				2.20
Forfeited (in dollars per share)				4.70
Outstanding at the end of the period (in dollars per share)	$ 0	$ 2.20	0	2.20
Exercisable at end of the period (in dollars per share)	$ 0	$ 0	$ 0	$ 0
Stock based compensation expenses	$ (35,000)	$ 121,000	$ (364,000)	$ (390,000)
Unrecognized stock-based compensation expenses	$ 0		$ 0

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

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Amount of cost to be recognized for option under share-based payment arrangement.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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