Quarterly report pursuant to Section 13 or 15(d)

Summary of Warrant Activity (Detail)

v3.21.2
Summary of Warrant Activity (Detail) - Warrants
shares in Thousands
6 Months Ended
Jun. 30, 2021
$ / shares
shares
Class Of Warrant Or Right [Line Items]  
Beginning Balance | shares 54,052
Exercised | shares (35,765)
Ending Balance | shares 18,287
Warrants exercisable at June 30, 2021 | shares 18,287
Vested warrants expired during the period ended June 30, 2021 | shares 0
Beginning Balance | $ / shares $ 0.62
Exercised | $ / shares 0.43
Ending Balance | $ / shares 1.00
Warrants exercisable at June 30, 2021 | $ / shares 1.00
Vested warrants expired during the period ended June 30, 2021 | $ / shares $ 0