Stockholders' equity - Schedule of warrants or rights (Detail) - $ / shares |
6 Months Ended | ||
|---|---|---|---|
Apr. 22, 2024 |
Dec. 31, 2025 |
Sep. 30, 2025 |
|
| Class of Warrant or Right [Line Items] | |||
| Outstanding, beginning of period | 20,443,496 | ||
| Pre-funded warrants issued | 5,749,152 | ||
| Outstanding, ending of period | 20,179,428 | ||
| Weighted Average Exercise Price, beginning of period | $ 0.9672 | ||
| Weighted Average Exercise Price, ending of period | $ 0.9738 | $ 0.9672 | |
| Series 2 Warrants [Member] | |||
| Class of Warrant or Right [Line Items] | |||
| Common warrants exercised | (63,792) | ||
| Pre-funded warrants exercised | $ 1.9299 | ||
| Pre-funded warrants [Member] | |||
| Class of Warrant or Right [Line Items] | |||
| Common warrants exercised | (200,276) | ||
| Pre-funded warrants exercised | $ 0.0001 |