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Share-Based Compensation - Additional Information (Details) - USD ($) |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended |  |
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Nov. 24, 2021 | Jun. 23, 2021 | Jun. 10, 2020 | Feb. 14, 2020 | Dec. 05, 2018 | May 18, 2017 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Mar. 14, 2018 | Nov. 18, 2015
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share options granted |  |  |  |  |  |  |  |  | 200,000 |  |  |
Employees and Directors |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Unvested employee options outstanding |  |  |  |  |  |  | 305,836 | 398,824 | 305,836 | 398,824 |  |
Employee Stock Option |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Expense recognized |  |  |  |  |  |  | $ 53,000 | $ 68,000 | $ 170,000 | $ 279,000 |  |
Unamortized compensation expense share options |  |  |  |  |  |  | 238,000 | $ 364,000 | $ 238,000 | $ 364,000 |  |
Vesting period |  |  |  |  |  |  |  |  | 2 years 7 months 17 days | 1 year 5 months 26 days |  |
Risk-free interest rate based on estimate of U.S. treasury yield |  |  |  |  |  |  |  |  | 7 years |  |  |
Restricted Share Units (RSUs) |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Benefit recognized related to share based compensation |  |  |  |  |  |  |  |  |  | $ 5,000 |  |
Expense recognized |  |  |  |  |  |  | $ 0 |  | $ 0 | $ 0 |  |
Number of shares outstanding |  |  |  |  |  |  | 0 | 0 | 0 | 0 |  |
Unamortized compensation expense |  |  |  |  |  |  | $ 0 | $ 0 | $ 0 | $ 0 |  |
Restricted Share Units (RSUs) | Employees and Directors |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares, granted/awarded |  |  |  |  |  |  |  |  | 0 | 0 |  |
Restricted Share Units (RSUs) | Director |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 1 year |  |  |
Options and Restricted Share Units |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 2 years 7 months 17 days | 1 year 5 months 26 days |  |
Unamortized compensation expense |  |  |  |  |  |  | $ 238,000 | $ 364,000 | $ 238,000 | $ 364,000 |  |
2015 Plan |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares authorized |  |  |  |  |  | 29,535 |  |  |  |  |  | 14,895
Increase in number of ordinary shares available for issuance |  |  |  |  |  | 14,640 |  |  |  |  |  |
2018 Plan |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of shares authorized |  | 1,295,819 |  |  |  |  |  |  |  |  | 67,897 |
Increase in number of ordinary shares available to be granted, percentage |  |  |  | 4.00% | 4.00% |  |  |  |  |  |  |
Increase in number of ordinary shares available to be granted |  | 1,000,000 | 150,000 | 39,650 | 38,272 |  |  |  |  |  |  |
2018 Plan | Restricted Share Units (RSUs) | Employees |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 2 years |  |  |
2021 Inducement Plan |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Increase in number of ordinary shares available to be granted | 333,333 |  |  |  |  |  |  |  |  |  |  |
2021 Inducement Plan | Restricted Share Units (RSUs) | Employees |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 4 years |  |  |
2015 Plan, 2018 Plan and 2021 Inducement Plan |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Share options granted |  |  |  |  |  |  |  |  | 200,000 |  |  |
2015 Plan, 2018 Plan and 2021 Inducement Plan | Employee Stock Option |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 4 years |  |  |
Vesting rights |  |  |  |  |  |  |  |  | The vesting requirement is conditioned upon a grantee’s continued service with the Company during the vesting period. Once vested, all awards are exercisable from the date of grant until they expire. The option grants are non-transferable. Vested options generally remain exercisable for 90 days subsequent to the termination of the option holder’s service with the Company. In the event of an option holder’s disability or death while employed by or providing service to the Company, the exercisable period extends to twelve months or eighteen months, respectively. |  |  |
Share option granted term |  |  |  |  |  |  |  |  | 10 years |  |  |
2015 Plan, 2018 Plan and 2021 Inducement Plan | Employee Stock Option | Director |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  | 1 year |  |  |

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