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Stock-Based Compensation (Tables)
 12 Months Ended
Dec. 31, 2020
Share-based Payment Arrangement, Noncash Expense [Abstract]  
Schedule of Weighted Average Grant-Date Fair Value of Stock Options
The weighted average grant-date fair value of stock options used in the calculation of stock-based compensation expense for the years ended December 31, 2020 and 2019 was calculated using the following assumptions:

Years Ended December 31,
 20202019
Risk-free interest rate0.8%1.9%
Expected dividend yield— — 
Expected option term10 years10 years
Volatility70.0 %72.4 %
Summary of Option Activity
A summary of option activity for the year ended December 31, 2020 is presented below:
Number of
Options		Weighted
Average
Exercise Price		Weighted
Average
Remaining
Contractual
Life (in years)		Aggregate
Intrinsic Value
Outstanding at December 31, 2019164,980 $7.16   
Granted
200,000 1.57   
Exercised
— —   
Forfeited
(2,996)31.57   
Expired
(28)5,875.19 
Outstanding at December 31, 2020361,956 $3.68 9.2$— 
Vested or expected to vest at December 31, 2020161,158 $6.25 8.5$— 
Exercisable at December 31, 2020161,158 $6.25 8.5$—