Stock-Based Compensation - Performance Based Stock Options (Details) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Weighted Average Exercise Price
Stock based compensation expenses	$ (236,000)	$ 935,000
Stock option awards - performance based awards
Number of Shares
Outstanding at the beginning of the period (in shares)	750,000	388,125
Outstanding at the end of the period (in shares)	750,000	388,125
Exercisable at end of period (in shares)	0	0
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 2.20	$ 4.70
Outstanding at the end of the period (in dollars per share)	2.20	4.70
Exercisable at end of the period (in dollars per share)	$ 0	$ 0
Stock based compensation expenses	$ (340,000)	$ 86,000
Unrecognized stock-based compensation expenses	$ 0

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

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