v3.20.2

Stockholders' Equity - Additional Information (Detail) - shares | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Equity [Abstract] |  |  |
Shares of common stock, authorized (in shares) |  | 600,000,000.0 |
Shares of common stock, issued and sold (in shares) |  | 191,800,000 |
Stock issued during period, shares, new issues (in shares) |  | 2,300,000 | 3,000,000.0
2018 Warrants |  |  |
Class of Stock [Line Items] |  |  |
Number of shares to be issued upon exercise of the Warrants (in shares) | 1,600,000 |  | 4,300,000

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