Annual report pursuant to Section 13 and 15(d)

Stock-based compensation. (Details) - Schedule of unvested restricted stock activity

v3.21.1
Stock-based compensation. (Details) - Schedule of unvested restricted stock activity
shares in Thousands
12 Months Ended
Dec. 31, 2020
$ / shares
shares
Schedule of unvested restricted stock activity [Abstract]  
Number of Shares, Unvested Beginning of the period | shares 2,201
Weighted Average Grant Date Fair Value Per Share, Unvested, Beginning of the period | $ / shares $ 1.84
Number of Shares, Issued | shares 1,663
Weighted Average Grant Date Fair Value Per Share, Issued | $ / shares $ 1.25
Number of Shares, Vested | shares (1,290)
Weighted Average Grant Date Fair Value Per Share, Vested | $ / shares $ 2.08
Number of Shares, Canceled | shares (314)
Weighted Average Grant Date Fair Value Per Share, Canceled | $ / shares $ 1.33
Number of Shares, Unvested Ending of the period | shares 2,260
Weighted Average Grant Date Fair Value Per Share, Unvested Ending of the period | $ / shares $ 1.34