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Stock Incentive Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended
	Jan. 31, 2025	Jun. 30, 2024	Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024	Dec. 31, 2023	Nov. 13, 2023	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)			12,374,230
Stock‑based compensation expense			$ 2,508	$ 1,431
Weighted average grant date fair value of stock options (in dollars per share)			$ 14.03	$ 15.79
Outstanding Series A Preferred Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total (in shares)			2,475,023
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting term			4 years
Weighted average period			3 years
Grants in period (in shares)			256,790
Grants in period (in dollars per share)			$ 16.93
Estimated forfeitures rate			10.00%
Unrecognized compensation expense			$ 8,000
Common stock \| Outstanding Series A Preferred Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to unvested employee stock options			$ 17,900
Weighted average period			3 years 2 months 12 days
2016 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants (in shares)										40,341
Number of shares authorized, increase (in shares)	1,030,694	3,466,544
Total (in shares)			3,598,149
Employment Inducement Incentive Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants (in shares)			489,683
Total (in shares)		360,000			450,000	60,833		66,667	39,166
Old Cartesian Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized for grants (in shares)			36,179
Award vesting term			4 years
Award expiration term			10 years
Unrecognized compensation expense related to unvested employee stock options							$ 2,600
Stock‑based compensation expense			$ 200	$ 400
Old Cartesian Plan \| Old Cartestian \| Common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, outstanding, number (in shares)							776,865
Old Cartesian Plan \| Old Cartestian \| Preferred stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, options, outstanding, number (in shares)							14,112.299