Contingent Obligations and Non-Current Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Government grant obligations	$ 11,124
Liabilities, current	600
Liabilities, Noncurrent	10,524
Post-retirement benefits obligations	1,840	$ 1,917
Reserves for potential future severance indemnity	$ 814	$ 702
Breath ID Products [Member]
Percent of breath ID revenue for grant repayment	3.00%
Maximum [Member]
Percentage of interest on grants	6.60%
Minimum [Member]
Percentage of interest on grants	0.58%