Contingent Obligations and Non-Current Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2022	Sep. 30, 2021
Government grant obligations	$ 5,588	$ 5,814
Breath ID Products [Member]
Percent of breath ID revenue for grant repayment	3.00%
Potential Future Severance Indemnity [Member]
Liability for potential severance indemnity	$ 713	754
Former Chief Executive Officer [Member]
Post employment benefit obligations	$ 1,589	$ 1,676
Maximum [Member] | Long Term Government Grant Obligations [Member]
Percentage of interest on grants	2.02%	2.02%
Minimum [Member] | Long Term Government Grant Obligations [Member]
Percentage of interest on grants	0.58%	0.58%