Revenue Recognition - Additional Information (Details) - USD ($)	3 Months Ended			12 Months Ended
	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation Of Revenue [Line Items]
Cost of sales				$ 58,884,000	$ 39,970,000
Unbilled receivables				1,051,000
Deferred contract costs				0	0
Revenue				75,864,000	34,136,000
Value of notes with customer				7,896,000	184,000
Cost of revenue				78,570,000	64,403,000
Secured Promissory Note
Disaggregation Of Revenue [Line Items]
Value of notes with customer			$ 10,000,000.0
Term of the notes			3 years
Monthly principal and interest payments			$ 300,000
Frequency of payments			monthly
Deferred Revenue and Other Liabilities
Disaggregation Of Revenue [Line Items]
Deferred contract liabilities				0	200,000
Deferred Contract Liability
Disaggregation Of Revenue [Line Items]
Revenue				0	200,000
Bureau of Customs and Border Patrol ("CBP")
Disaggregation Of Revenue [Line Items]
Awarded contract amount		$ 10,500,000
Increase in contract amount		$ 300,000
Revenue recognized under the contract				300,000	10,100,000
Unbilled receivables				1,100,000
Revenue for unsatisfied performance obligations				100,000
Shipping and Handling
Disaggregation Of Revenue [Line Items]
Cost of sales				400,000	$ 300,000
Product
Disaggregation Of Revenue [Line Items]
Revenue	$ 12,500,000		$ 0
Partially financed product sale			12,500,000
Cost of revenue			$ 0
Payments received from customer				$ 7,200,000