Fair value measurements - Narrative (Details) - Common Stock Warrants	Sep. 30, 2024 $ / shares yr	Aug. 13, 2024 $ / shares	Mar. 15, 2024 $ / shares
Class of Warrant or Right [Line Items]
Exercise price of warrants (in dollars per share)		$ 1.03	$ 1.45
Expected Dividend Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0
Measurement Input, Exercise Price | Minimum
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0.50
Measurement Input, Exercise Price | Maximum
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	1.03
Measurement Input, Share Price
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0.52
Measurement Input, Price Volatility
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0.857
Risk Free Interest Rate
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input	0.037
Measurement Input, Expected Term
Class of Warrant or Right [Line Items]
Warrants and rights outstanding, measurement input | yr	7