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v3.26.1

Nature of Business and Basis of Presentation (Details) $ / shares in Units, $ in Thousands | 3 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2025 subsidiary | Dec. 31, 2026 £ / shares | Dec. 31, 2026 USD ($) $ / shares shares | Jun. 30, 2026 £ / shares | Jun. 30, 2026 USD ($) | Dec. 31, 2025 £ / shares | Dec. 31, 2025 USD ($) | Sep. 29, 2025 | Jun. 30, 2025 USD ($) | Dec. 31, 2024 USD ($)
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Number of new subsidiaries | subsidiary | 2 |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value (per share) | £ / shares |  |  |  | £ 0.000025 |  | £ 0.000025 |  |  |  |
Merger agreement extension period |  |  |  |  |  |  |  | 60 days |  |
Cash, cash equivalents and restricted cash | $ |  |  |  |  | $ 59,630 |  | $ 71,852 |  | $ 87,784 | $ 112,400
Accumulated deficit | $ |  |  |  |  | $ 320,208 |  | $ 304,092 |  |  |
Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value (per share) | £ / shares |  | £ 0.000025 |  |  |  |  |  |  |  |
Number of depositary shares per share of common stock (in shares) | shares |  |  | 1 |  |  |  |  |  |  |
Scheme Shares | Minimum | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Stock conversion ratio |  |  | 0.1 |  |  |  |  |  |  |
Scheme Shares | Maximum | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Stock conversion ratio |  |  | 0.166667 |  |  |  |  |  |  |
Clywedog Capital Stock | Minimum | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Stock conversion ratio |  |  | 0.000305 |  |  |  |  |  |  |
Clywedog Capital Stock | Maximum | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Stock conversion ratio |  |  | 0.000508 |  |  |  |  |  |  |
Topco | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value (per share) | $ / shares |  |  | $ 0.0001 |  |  |  |  |  |  |
Self-tender offer authorized amount to purchase | $ |  |  | $ 27,000 |  |  |  |  |  |  |
Clywedog | Forecast |  |  |  |  |  |  |  |  |  |
Share Repurchase Program [Line Items] |  |  |  |  |  |  |  |  |  |
Ordinary shares, nominal value (per share) | $ / shares |  |  | $ 0.0001 |  |  |  |  |  |  |
Preferred stock par value (in dollars per share) | $ / shares |  |  | $ 0.0001 |  |  |  |  |  |  |

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