Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 26,543	$ 19,242	$ 47,595	$ 40,541
Revenue from Contract with Customer | Customer Concentration Risk | Transferred over Time
Disaggregation of Revenue [Line Items]
Concentration risk			40.00%	49.00%
North America
Disaggregation of Revenue [Line Items]
Revenue	20,514	14,353	$ 35,988	$ 31,647
Europe
Disaggregation of Revenue [Line Items]
Revenue	6,029	4,889	11,607	8,894
Fixed wing aircraft
Disaggregation of Revenue [Line Items]
Revenue	10,080	8,855	20,019	19,581
Rotorcraft
Disaggregation of Revenue [Line Items]
Revenue	4,197	3,513	7,347	7,894
Energy components for power generation units
Disaggregation of Revenue [Line Items]
Revenue	6,470	5,101	12,661	9,724
Commercial product and other revenue
Disaggregation of Revenue [Line Items]
Revenue	5,796	1,773	7,568	3,342
Commercial revenue
Disaggregation of Revenue [Line Items]
Revenue	17,376	11,361	30,616	21,542
Military revenue
Disaggregation of Revenue [Line Items]
Revenue	$ 9,167	$ 7,881	$ 16,979	$ 18,999