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Organization and Basis of Presentation (Details)						1 Months Ended	3 Months Ended		15 Months Ended
Organization and Basis of Presentation (Details)	Apr. 20, 2026	Apr. 17, 2026 USD ($)	Apr. 15, 2026 USD ($)	Nov. 07, 2025 USD ($)	Mar. 09, 2025 USD ($) shares	Apr. 30, 2026 USD ($)	Mar. 31, 2026 USD ($) clinic	Mar. 31, 2025 USD ($)	Mar. 31, 2026 USD ($) clinic	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of late stage clinical programs \| clinic							4		4
Number of GMP-Licensed							2		2
Minimum development period of proprietary manufacturing platform							9 years
Minimum number of distinct viral vectors utilized							20		20
Future contingent consideration							$ 920,000	$ 615,000
Accumulated deficit							862,536,000		$ 862,536,000	$ 816,223,000
Cash flows from operations							17,810,000	(36,828,000)
Cash, cash equivalents							73,758,000	68,610,000	73,758,000	68,193,000	$ 105,668,000
Proceeds from the issuance of ordinary shares							14,027,000	$ 4,482,000
Outstanding debt obligation							24,866,000		24,866,000	$ 24,648,000
Perceptive Credit Holdings \| Secured Debt
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Outstanding debt obligation							25,000,000		25,000,000
Hologen Strategic Agreement \| Hologen Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone funding upfront payment received					$ 200,000,000				105,000,000
Hologen Limited \| Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Class A shares of Hologen received in transaction \| shares					500,000
Hologen Limited \| Hologen Strategic Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone funding upfront payment received									105,000,000
Additional funding payment received							105,000,000
Milestone payment to be received							$ 95,000,000		$ 95,000,000
Eli Lilly \| Eli Lilly Collaboration Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Initial funding				$ 75,000,000
Contingent funding available				400,000,000
Milestone funding contingent on development and regulatory approval				$ 135,000,000
Maximum \| Hologen Strategic Agreement \| Hologen Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone funding to provide additional capital					$ 230,000,000
Subsequent Event \| Public Offering
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Proceeds from the issuance of ordinary shares		$ 100,000,000
Net proceeds from issuance of common stock, net		$ 93,300,000
Subsequent Event \| Research, Development And Other Assets
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront cash payment			$ 25,000,000
Future contingent consideration			50,000,000
Sales threshold payment			$ 250,000,000
Subsequent Event \| Hologen Neuro AI Limited \| MeiraGTx Neuro UK Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Percentage of issued share capital	30.00%
Subsequent Event \| Hologen Neuro AI Limited \| Hologen Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Minority interest ownership percentage	70.00%
Subsequent Event \| MeiraGTx Manufacturing Limited \| JJDC
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of business days			5 days
Subsequent Event \| MeiraGTx Manufacturing Limited \| Hologen Limited
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Maximum ownership percentage	40.00%
Agreement, Option exercise period	3 years
Subsequent Event \| Asset Purchase Agreement \| JJDC
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Ownership interest			5.00%
Subsequent Event \| Hologen Limited \| Hologen Strategic Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Milestone funding upfront payment received						$ 105,000,000