Fair Value Measurements - Common stock warrants (Details)	Dec. 31, 2025 $ / shares USD ($)	Sep. 30, 2025 $ / shares USD ($)
Risk-free interest rate
Fair value inputs
Warrant inputs	0.0357	0.0364
Term
Fair value inputs
Warrant inputs | $	3.2	3.5
Expected volatility
Fair value inputs
Warrant inputs	1.535	1.486
Stock price (in dollars per share)
Fair value inputs
Warrant inputs | $ / shares	1.58	1.06