Stock-Based Compensation - Performance Based Stock Options (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Weighted Average Exercise Price
Stock based compensation expenses	$ 433,000	$ (1,461,000)	$ 197,000	$ (526,000)
Stock option awards - performance based awards
Number of Shares
Outstanding at the beginning of the period (in shares)			750,000	388,125
Granted (in shares)				600,000
Forfeited (in shares)				(388,125)
Expired (in shares)			(375,000)
Outstanding at the end of the period (in shares)	375,000	600,000	375,000	600,000
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
Granted (in dollars per share)				2.45
Forfeited (in dollars per share)				4.70
Expired (in dollar per share)			2.20
Outstanding at the end of the period (in dollars per share)	$ 2.20	$ 2.45	2.20	2.45
Exercisable at end of the period (in dollars per share)	$ 0	$ 0	$ 0	$ 0
Stock based compensation expenses	$ 11,000	$ (596,000)	$ (330,000)	$ (511,000)
Unrecognized stock-based compensation expenses	$ 0		$ 0