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Stockholders' Equity - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Dec. 31, 2021 | Sep. 30, 2020 | Dec. 31, 2021 | Dec. 31, 2020 | Jun. 30, 2021 | Nov. 10, 2020
Class of Stock [Line Items] |  |  |  |  |  |
Fair value of warrants | $ 14,309,000 |  | $ 14,309,000 |  | $ 22,355,000 |
Payments of Stock Issuance Costs |  |  | 3,672,000 | $ 64,000 |  |
Common stock Value Issued | 48,653,000 | $ 3,136,000 |  |  |  |
Unsold Securities Shares and Warrants Under Agreement |  |  | 107,500,000 |  |  |
Aggregate Value of Securities Available Under Agreement | $ 123,400,000 |  | $ 123,400,000 |  |  |
Warrant [Member] |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Exercise price | $ 2.54 |  | $ 2.54 |  |  |
Warrants outstanding | 16,058,985 |  | 16,058,985 |  |  |
Underwritten Registered Offering |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Common stock share issued |  |  | 20,125,000,000 |  |  |
Shares Issued, Price Per Share | $ 2.60 |  | $ 2.60 |  |  |
Proceeds from Issuance Initial Public Offering |  |  | $ 48,700,000 |  |  |
Payments of Stock Issuance Costs |  |  | 3,700,000 |  |  |
ATM Sales Agreement |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Common stock share issued |  |  |  | 958,083,000 |  |
Common stock Value Issued |  |  |  | $ 3,100,000 |  |
Aggregate Value of Securities Available Under Agreement |  |  |  | 100,000 |  |
Gross Proceeds From Issuance of Common Stock |  |  |  | $ 3,200 |  |
Two Thousand And Twenty At The Market Sale Agreement |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Aggregate value of securities available under shelf registration statement | $ 60,000,000.0 |  | 60,000,000.0 |  |  |
Maximum |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Sale of shares and warrants under agreement |  |  | 200,000,000.0 |  |  |
Maximum | Two Thousand And Twenty At The Market Sale Agreement |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |
Sale of shares under agreement | $ 60,000,000.0 |  | $ 60,000,000.0 |  |  | $ 60,000,000.0

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